diff --git a/src/components/Chat.tsx b/src/components/Chat.tsx
index f93380d..888ab59 100644
--- a/src/components/Chat.tsx
+++ b/src/components/Chat.tsx
@@ -4,6 +4,7 @@ import { ChatInput } from './ChatInput';
 import { TypingIndicator } from './TypingIndicator';
 import type { ChatMessage, ConnectionStatus } from '../types';
 import { Bot, ArrowDown, Loader2, ChevronsDownUp, ChevronsUpDown } from 'lucide-react';
+import { MessageSearch } from './MessageSearch';
 import { useT } from '../hooks/useLocale';
 import { getLocale, type TranslationKey } from '../lib/i18n';
 import { useToolCollapse } from '../hooks/useToolCollapse';
@@ -131,8 +132,61 @@ export function Chat({ messages, isGenerating, isLoadingHistory, status, session
   const { globalState, collapseAll, expandAll } = useToolCollapse();
   const hasToolCalls = useMemo(() => messages.some(m => m.blocks.some(b => b.type === 'tool_use' || b.type === 'tool_result')), [messages]);
 
+  // Message search
+  const [searchOpen, setSearchOpen] = useState(false);
+  const [searchQuery, setSearchQuery] = useState('');
+  const [searchActiveIndex, setSearchActiveIndex] = useState(0);
+  // Compute matches: list of message IDs containing the query
+  const searchMatches = useMemo(() => {
+    if (!searchQuery.trim()) return [] as string[];
+    const q = searchQuery.toLowerCase();
+    return visibleMessages
+      .filter(({ msg }) => {
+        const content = msg.content?.toLowerCase() || '';
+        if (content.includes(q)) return true;
+        return msg.blocks.some(b => {
+          if (b.type === 'text' || b.type === 'thinking') return b.text.toLowerCase().includes(q);
+          if (b.type === 'tool_result') return b.content.toLowerCase().includes(q);
+          return false;
+        });
+      })
+      .map(({ msg }) => msg.id);
+  }, [visibleMessages, searchQuery]);
+
+  const handleSearch = useCallback((query: string, activeIndex: number) => {
+    setSearchQuery(query);
+    setSearchActiveIndex(activeIndex);
+  }, []);
+
+  // Scroll to active match
+  useEffect(() => {
+    if (searchMatches.length === 0) return;
+    const id = searchMatches[searchActiveIndex];
+    if (!id) return;
+    const el = scrollContainerRef.current?.querySelector(`[data-msg-id="${id}"]`);
+    el?.scrollIntoView({ behavior: 'smooth', block: 'center' });
+  }, [searchActiveIndex, searchMatches]);
+
+  const closeSearch = useCallback(() => {
+    setSearchOpen(false);
+    setSearchQuery('');
+  }, []);
+
+  // Ctrl+F handler
+  useEffect(() => {
+    const handler = (e: KeyboardEvent) => {
+      if ((e.metaKey || e.ctrlKey) && e.key === 'f') {
+        e.preventDefault();
+        setSearchOpen(true);
+      }
+    };
+    window.addEventListener('keydown', handler);
+    return () => window.removeEventListener('keydown', handler);
+  }, []);
+
   return (
     <div className="flex-1 flex flex-col min-h-0 relative">
+      <MessageSearch open={searchOpen} onClose={closeSearch} onSearch={handleSearch} matchCount={searchMatches.length} />
       <div ref={scrollContainerRef} className="flex-1 overflow-y-auto overflow-x-hidden relative" role="log" aria-label={t('chat.messages')} aria-live="polite">
         <div className="max-w-4xl mx-auto py-4 w-full">
           {messages.length === 0 && isLoadingHistory && (
@@ -153,8 +207,10 @@ export function Chat({ messages, isGenerating, isLoadingHistory, status, session
               <div className="text-sm mt-1 text-pc-text-muted">{t('chat.welcomeSub')}</div>
             </div>
           )}
-          {visibleMessages.map(({ msg, showSep }) => (
-                <div key={msg.id}>
+          {visibleMessages.map(({ msg, showSep }) => {
+            const isActiveMatch = searchMatches.length > 0 && searchMatches[searchActiveIndex] === msg.id;
+            return (
+                <div key={msg.id} data-msg-id={msg.id}>
                   {showSep && (
                     <div className="flex items-center gap-3 py-3 px-4 select-none" aria-label={formatDateSeparator(msg.timestamp, t)}>
                       <div className="flex-1 h-px bg-[var(--pc-hover-strong)]" />
@@ -162,9 +218,12 @@ export function Chat({ messages, isGenerating, isLoadingHistory, status, session
                       <div className="flex-1 h-px bg-[var(--pc-hover-strong)]" />
                     </div>
                   )}
-                  <ChatMessageComponent message={msg} onRetry={!isGenerating ? handleSend : undefined} agentAvatarUrl={agentAvatarUrl} />
+                  <div className={isActiveMatch ? 'ring-1 ring-pc-accent-light/40 rounded-lg' : ''}>
+                    <ChatMessageComponent message={msg} onRetry={!isGenerating ? handleSend : undefined} agentAvatarUrl={agentAvatarUrl} />
+                  </div>
                 </div>
-          ))}
+            );
+          })}
           {showTyping && <TypingIndicator />}
           <div ref={bottomRef} />
         </div>
diff --git a/src/components/KeyboardShortcuts.tsx b/src/components/KeyboardShortcuts.tsx
index f4a34a8..c01b637 100644
--- a/src/components/KeyboardShortcuts.tsx
+++ b/src/components/KeyboardShortcuts.tsx
@@ -90,6 +90,10 @@ export function KeyboardShortcuts({ open, onClose }: Props) {
               keys={<Kbd>Esc</Kbd>}
               label={t('shortcuts.stop')}
             />
+            <ShortcutRow
+              keys={<><Kbd>{mod}</Kbd><span className="text-pc-text-faint">+</span><Kbd>F</Kbd></>}
+              label={t('shortcuts.searchMessages')}
+            />
           </div>
 
           <div className="py-3">
diff --git a/src/components/MessageSearch.tsx b/src/components/MessageSearch.tsx
new file mode 100644
index 0000000..8b78ca6
--- /dev/null
+++ b/src/components/MessageSearch.tsx
@@ -0,0 +1,98 @@
+import { useState, useEffect, useRef, useCallback } from 'react';
+import { Search, X, ChevronUp, ChevronDown } from 'lucide-react';
+import { useT } from '../hooks/useLocale';
+
+interface Props {
+  open: boolean;
+  onClose: () => void;
+  onSearch: (query: string, activeIndex: number) => void;
+  matchCount: number;
+}
+
+export function MessageSearch({ open, onClose, onSearch, matchCount }: Props) {
+  const t = useT();
+  const [query, setQuery] = useState('');
+  const [activeIndex, setActiveIndex] = useState(0);
+  const inputRef = useRef<HTMLInputElement>(null);
+
+  useEffect(() => {
+    if (open) {
+      inputRef.current?.focus();
+      inputRef.current?.select();
+    }
+  }, [open]);
+
+  useEffect(() => {
+    onSearch(query, activeIndex);
+  }, [query, activeIndex, onSearch]);
+
+  // Reset active index when query changes
+  useEffect(() => {
+    setActiveIndex(0);
+  }, [query]);
+
+  const navigate = useCallback((dir: 1 | -1) => {
+    if (matchCount === 0) return;
+    setActiveIndex(prev => {
+      const next = prev + dir;
+      if (next < 0) return matchCount - 1;
+      if (next >= matchCount) return 0;
+      return next;
+    });
+  }, [matchCount]);
+
+  const handleKeyDown = useCallback((e: React.KeyboardEvent) => {
+    if (e.key === 'Escape') {
+      onClose();
+    } else if (e.key === 'Enter') {
+      e.preventDefault();
+      navigate(e.shiftKey ? -1 : 1);
+    }
+  }, [onClose, navigate]);
+
+  if (!open) return null;
+
+  return (
+    <div className="absolute top-2 right-4 z-20 flex items-center gap-1.5 rounded-xl border border-pc-border-strong bg-pc-elevated/95 backdrop-blur-lg px-3 py-1.5 shadow-lg">
+      <Search size={14} className="text-pc-text-muted shrink-0" />
+      <input
+        ref={inputRef}
+        type="text"
+        value={query}
+        onChange={e => setQuery(e.target.value)}
+        onKeyDown={handleKeyDown}
+        placeholder={t('search.placeholder')}
+        className="bg-transparent text-sm text-pc-text placeholder:text-pc-text-muted outline-none w-48"
+        aria-label={t('search.placeholder')}
+      />
+      {query && (
+        <span className="text-xs text-pc-text-muted whitespace-nowrap">
+          {matchCount > 0 ? `${activeIndex + 1}/${matchCount}` : t('search.noResults')}
+        </span>
+      )}
+      <button
+        onClick={() => navigate(-1)}
+        disabled={matchCount === 0}
+        className="p-1 rounded-lg text-pc-text-muted hover:text-pc-text hover:bg-[var(--pc-hover)] disabled:opacity-30 transition-colors"
+        aria-label={t('search.prev')}
+      >
+        <ChevronUp size={14} />
+      </button>
+      <button
+        onClick={() => navigate(1)}
+        disabled={matchCount === 0}
+        className="p-1 rounded-lg text-pc-text-muted hover:text-pc-text hover:bg-[var(--pc-hover)] disabled:opacity-30 transition-colors"
+        aria-label={t('search.next')}
+      >
+        <ChevronDown size={14} />
+      </button>
+      <button
+        onClick={onClose}
+        className="p-1 rounded-lg text-pc-text-muted hover:text-pc-text hover:bg-[var(--pc-hover)] transition-colors"
+        aria-label={t('shortcuts.close')}
+      >
+        <X size={14} />
+      </button>
+    </div>
+  );
+}
diff --git a/src/lib/i18n.ts b/src/lib/i18n.ts
index 1ee22f4..608a3c5 100644
--- a/src/lib/i18n.ts
+++ b/src/lib/i18n.ts
@@ -110,6 +110,13 @@ const en = {
   'theme.dark': 'Dark',
   'theme.light': 'Light',
   'theme.oled': 'OLED',
+
+  // Message search
+  'search.placeholder': 'Search messages…',
+  'search.noResults': '0 results',
+  'search.prev': 'Previous match',
+  'search.next': 'Next match',
+  'shortcuts.searchMessages': 'Search messages',
 } as const;
 
 const fr: Record<keyof typeof en, string> = {
@@ -202,6 +209,12 @@ const fr: Record<keyof typeof en, string> = {
   'theme.dark': 'Sombre',
   'theme.light': 'Clair',
   'theme.oled': 'OLED',
+
+  'search.placeholder': 'Rechercher dans les messages…',
+  'search.noResults': '0 résultat',
+  'search.prev': 'Résultat précédent',
+  'search.next': 'Résultat suivant',
+  'shortcuts.searchMessages': 'Rechercher dans les messages',
 };
 
 export type TranslationKey = keyof typeof en;