diff --git a/internal/handlers/handlers.go b/internal/handlers/handlers.go
index 503799b..eacfbf5 100644
--- a/internal/handlers/handlers.go
+++ b/internal/handlers/handlers.go
@@ -547,3 +547,104 @@ func (h *Handlers) TreeAPIHandler(c *gin.Context) {
 
 	c.JSON(http.StatusOK, notesTree)
 }
+
+// SearchHandler performs a simple full-text search across markdown and allowed text files
+// within the notes directory, honoring skipped directories.
+// GET /api/search?q=term
+func (h *Handlers) SearchHandler(c *gin.Context) {
+	query := strings.TrimSpace(c.Query("q"))
+	if query == "" {
+		c.JSON(http.StatusBadRequest, gin.H{"error": "missing query"})
+		return
+	}
+
+	// Case-insensitive search
+	qLower := strings.ToLower(query)
+
+	type Snippet struct {
+		Line    int    `json:"line"`
+		Preview string `json:"preview"`
+	}
+	type Result struct {
+		Path     string    `json:"path"`
+		Type     string    `json:"type"` // "md" or "text"
+		Snippets []Snippet `json:"snippets"`
+	}
+
+	results := make([]Result, 0, 32)
+
+	// Walk the notes directory
+	err := filepath.Walk(h.config.NotesDir, func(path string, info os.FileInfo, err error) error {
+		if err != nil {
+			return nil // skip on error
+		}
+		if info.IsDir() {
+			// Compute relative dir path to check skip list
+			rel, _ := filepath.Rel(h.config.NotesDir, path)
+			rel = filepath.ToSlash(rel)
+			if rel == "." {
+				rel = ""
+			}
+			if utils.IsPathInSkippedDirs(rel, h.config.NotesDirSkip) {
+				return filepath.SkipDir
+			}
+			return nil
+		}
+
+		// Compute relative file path
+		relPath, _ := filepath.Rel(h.config.NotesDir, path)
+		relPath = filepath.ToSlash(relPath)
+
+		// Skip disallowed files
+		ext := strings.ToLower(filepath.Ext(relPath))
+		isMD := ext == ".md"
+		if !isMD && !models.IsAllowedFile(relPath, h.config.AllowedFileExtensions) {
+			return nil
+		}
+
+		// Read file content (limit size to prevent huge memory usage)
+		data, readErr := os.ReadFile(path)
+		if readErr != nil {
+			return nil
+		}
+		content := string(data)
+		contentLower := strings.ToLower(content)
+		if !strings.Contains(contentLower, qLower) {
+			return nil
+		}
+
+		// Build snippets: show up to 3 matches with 2 lines of context
+		lines := strings.Split(content, "\n")
+		linesLower := strings.Split(contentLower, "\n")
+		snippets := make([]Snippet, 0, 3)
+		for i := 0; i < len(linesLower) && len(snippets) < 3; i++ {
+			if strings.Contains(linesLower[i], qLower) {
+				start := i - 2
+				if start < 0 {
+					start = 0
+				}
+				end := i + 2
+				if end >= len(lines) {
+					end = len(lines) - 1
+				}
+				// Join preview lines
+				preview := strings.Join(lines[start:end+1], "\n")
+				snippets = append(snippets, Snippet{Line: i + 1, Preview: preview})
+			}
+		}
+
+		rtype := "text"
+		if isMD {
+			rtype = "md"
+		}
+		results = append(results, Result{Path: relPath, Type: rtype, Snippets: snippets})
+		return nil
+	})
+
+	if err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+		return
+	}
+
+	c.JSON(http.StatusOK, gin.H{"query": query, "results": results})
+}
diff --git a/internal/server/server.go b/internal/server/server.go
index 0cd4f64..a6456c5 100644
--- a/internal/server/server.go
+++ b/internal/server/server.go
@@ -96,6 +96,7 @@ func (s *Server) setupRoutes() {
 
 	// API routes
 	s.router.GET("/api/tree", h.TreeAPIHandler)
+	s.router.GET("/api/search", h.SearchHandler)
 }
 
 func (s *Server) setupStaticFiles() {
diff --git a/web/templates/base.html b/web/templates/base.html
index 7722a83..614cabf 100644
--- a/web/templates/base.html
+++ b/web/templates/base.html
@@ -265,7 +265,10 @@
                 <div class="flex items-center justify-between">
                     <h1 class="sidebar-title text-xl font-bold text-white">{{.app_name}}</h1>
                     <div class="flex items-center space-x-2 items-center">
-                        <div class="sidebar-actions flex items-center space-x-2">
+                        <div class="sidebar-actions flex items-center space-x-3">
+                            <button id="open-search" class="text-gray-400 hover:text-white transition-colors" title="Search" aria-label="Search">
+                                <i class="fas fa-magnifying-glass"></i>
+                            </button>
                             <a href="/settings" class="text-gray-400 hover:text-white transition-colors" title="Settings">
                                 <i class="fas fa-cog"></i>
                             </a>
@@ -334,6 +337,26 @@
         </div>
     </div>
 
+    <!-- Search Modal -->
+    <div id="search-modal" class="modal-overlay hidden">
+        <div class="modal-content w-full max-w-3xl">
+            <div class="flex items-center mb-3">
+                <div class="relative flex-1">
+                    <i class="fas fa-magnifying-glass absolute left-3 top-3 text-gray-400"></i>
+                    <input id="search-input" type="text" placeholder="Search notes..." class="form-input pl-9 w-full" />
+                </div>
+                <button id="clear-search" class="ml-2 px-3 py-2 rounded bg-red-600 hover:bg-red-700 text-white" title="Clear">
+                    Clear
+                </button>
+                <button id="close-search" class="btn-secondary ml-2" title="Close">
+                    <i class="fas fa-xmark"></i>
+                </button>
+            </div>
+            <div id="search-status" class="text-sm text-gray-400 mb-2"></div>
+            <div id="search-results" class="space-y-3"></div>
+        </div>
+    </div>
+
     <!-- Scripts -->
     <script>
         // Initialize syntax highlighting
@@ -441,6 +464,118 @@
 
             // Expand active path in tree
             expandActivePath();
+
+            // Search modal wiring
+            const searchModal = document.getElementById('search-modal');
+            const openSearchBtn = document.getElementById('open-search');
+            const closeSearchBtn = document.getElementById('close-search');
+            const clearSearchBtn = document.getElementById('clear-search');
+            const searchInput = document.getElementById('search-input');
+            const searchResults = document.getElementById('search-results');
+            const searchStatus = document.getElementById('search-status');
+
+            const LS_KEY_QUERY = 'globalSearch:query';
+
+            function openSearch() {
+                if (!searchModal) return;
+                searchModal.classList.remove('hidden');
+                setTimeout(() => searchInput && searchInput.focus(), 0);
+                const lastQuery = localStorage.getItem(LS_KEY_QUERY) || '';
+                if (searchInput) {
+                    searchInput.value = lastQuery;
+                    if (lastQuery) doSearch(lastQuery);
+                }
+            }
+            function closeSearch() {
+                if (!searchModal) return;
+                searchModal.classList.add('hidden');
+            }
+            function clearSearch() {
+                if (!searchInput) return;
+                searchInput.value = '';
+                localStorage.removeItem(LS_KEY_QUERY);
+                renderResults({ query: '', results: [] });
+            }
+
+            let debounceTimer = null;
+            function debounce(fn, delay) {
+                return function(...args) {
+                    clearTimeout(debounceTimer);
+                    debounceTimer = setTimeout(() => fn.apply(this, args), delay);
+                }
+            }
+
+            function escapeHTML(str) {
+                return str.replace(/[&<>"']/g, s => ({'&':'&amp;','<':'&lt;','>':'&gt;','"':'&quot;','\'':'&#39;'}[s]));
+            }
+
+            function renderResults(data) {
+                if (!searchResults || !searchStatus) return;
+                searchResults.innerHTML = '';
+                if (!data || !data.results) {
+                    searchStatus.textContent = '';
+                    return;
+                }
+                searchStatus.textContent = `${data.results.length} result(s)`;
+                data.results.forEach(r => {
+                    const item = document.createElement('div');
+                    item.className = 'p-3 bg-slate-700 rounded border border-slate-600';
+                    const title = document.createElement('div');
+                    title.className = 'flex items-center justify-between text-sm text-blue-300 hover:text-blue-200 cursor-pointer';
+                    title.innerHTML = `<span><i class="fas ${r.type === 'md' ? 'fa-file-lines' : 'fa-file'} mr-2"></i>${escapeHTML(r.path)}</span>`;
+                    title.addEventListener('click', () => {
+                        const url = r.path.endsWith('.md') ? `/note/${r.path}` : `/view_text/${r.path}`;
+                        // remember query
+                        if (searchInput) localStorage.setItem(LS_KEY_QUERY, searchInput.value.trim());
+                        window.location.href = url;
+                    });
+                    item.appendChild(title);
+
+                    (r.snippets || []).forEach(snip => {
+                        const pre = document.createElement('pre');
+                        pre.className = 'mt-2 bg-slate-800 p-2 rounded text-xs whitespace-pre-wrap border border-slate-600';
+                        pre.textContent = `Line ${snip.line}:\n` + snip.preview;
+                        item.appendChild(pre);
+                    });
+                    searchResults.appendChild(item);
+                });
+            }
+
+            const doSearch = debounce(async function(q) {
+                const query = (q || '').trim();
+                if (!query) {
+                    renderResults({ query: '', results: [] });
+                    return;
+                }
+                try {
+                    searchStatus.textContent = 'Searching...';
+                    const res = await fetch(`/api/search?q=${encodeURIComponent(query)}`);
+                    const data = await res.json();
+                    if (res.ok) {
+                        localStorage.setItem(LS_KEY_QUERY, query);
+                        renderResults(data);
+                    } else {
+                        searchStatus.textContent = data.error || 'Search failed';
+                    }
+                } catch (e) {
+                    searchStatus.textContent = 'Search failed';
+                }
+            }, 250);
+
+            if (openSearchBtn) openSearchBtn.addEventListener('click', openSearch);
+            if (closeSearchBtn) closeSearchBtn.addEventListener('click', closeSearch);
+            if (clearSearchBtn) clearSearchBtn.addEventListener('click', clearSearch);
+            if (searchInput) searchInput.addEventListener('input', (e) => doSearch(e.target.value));
+
+            // Close modal on overlay click (but not when clicking inside content)
+            if (searchModal) {
+                searchModal.addEventListener('click', (e) => {
+                    if (e.target === searchModal) closeSearch();
+                });
+                document.addEventListener('keydown', (e) => {
+                    if (e.key === 'Escape' && !searchModal.classList.contains('hidden')) closeSearch();
+                });
+            }
         });
     </script>