diff --git a/.changeset/chat-header-git-diff-stats.md b/.changeset/chat-header-git-diff-stats.md
new file mode 100644
index 000000000..e79ab99a1
--- /dev/null
+++ b/.changeset/chat-header-git-diff-stats.md
@@ -0,0 +1,5 @@
+---
+"@moonshot-ai/kimi-web": minor
+---
+
+Show git diff line stats in the chat header using green `+N` and red `-N` counts, with a placeholder prop ready for backend wiring.
diff --git a/apps/kimi-web/src/App.vue b/apps/kimi-web/src/App.vue
index 7f0138f68..6838a482c 100644
--- a/apps/kimi-web/src/App.vue
+++ b/apps/kimi-web/src/App.vue
@@ -638,6 +638,7 @@ function openPr(url: string): void {
       :compaction="client.compaction.value"
       :workspace-name="client.visibleWorkspace.value?.name"
       :workspace-root="client.visibleWorkspace.value?.root ?? client.status.value.cwd"
+      :git-diff-stats="null"
       :workspaces="client.workspacesView.value"
       :active-workspace-id="client.activeWorkspaceId.value"
       :session-title="activeSessionTitle"
diff --git a/apps/kimi-web/src/components/ChatHeader.vue b/apps/kimi-web/src/components/ChatHeader.vue
index a84108dc8..3065a4cc3 100644
--- a/apps/kimi-web/src/components/ChatHeader.vue
+++ b/apps/kimi-web/src/components/ChatHeader.vue
@@ -19,6 +19,8 @@ const props = defineProps<{
   ahead?: number;
   behind?: number;
   changesCount?: number;
+  /** Git diff line stats: additions / deletions. Zero/null values are hidden. */
+  gitDiffStats?: { totalAdditions: number; totalDeletions: number } | null;
   isGitRepo?: boolean;
   /** GitHub PR for the current branch, when known (null/undefined = none). */
   pr?: { number: number; state: string; url: string } | null;
@@ -38,6 +40,9 @@ const emit = defineEmits<{
 const ahead = computed(() => props.ahead ?? 0);
 const behind = computed(() => props.behind ?? 0);
 const changes = computed(() => props.changesCount ?? 0);
+const adds = computed(() => props.gitDiffStats?.totalAdditions ?? 0);
+const dels = computed(() => props.gitDiffStats?.totalDeletions ?? 0);
+const hasLineStats = computed(() => adds.value > 0 || dels.value > 0);
 
 // ---------------------------------------------------------------------------
 // More-menu (kebab dropdown)
@@ -265,7 +270,11 @@ function startArchive(): void {
       <span class="ch-branch">{{ branch }}</span>
       <span v-if="ahead > 0" class="ch-ahead">↑{{ ahead }}</span>
       <span v-if="behind > 0" class="ch-behind">↓{{ behind }}</span>
-      <span v-if="changes > 0" class="ch-changes">{{ t('header.changed', { n: changes }) }}</span>
+      <template v-if="hasLineStats">
+        <span v-if="adds > 0" class="ch-add">+{{ adds }}</span>
+        <span v-if="dels > 0" class="ch-del">-{{ dels }}</span>
+      </template>
+      <span v-else-if="changes > 0" class="ch-changes">{{ t('header.changed', { n: changes }) }}</span>
     </div>
 
     <!-- GitHub PR status -->
@@ -342,6 +351,14 @@ function startArchive(): void {
   flex: none;
   color: var(--warn);
 }
+.ch-add {
+  flex: none;
+  color: var(--ok);
+}
+.ch-del {
+  flex: none;
+  color: var(--err);
+}
 .ch-spacer { flex: 1; min-width: 0; }
 
 .ch-act {
diff --git a/apps/kimi-web/src/components/ConversationPane.vue b/apps/kimi-web/src/components/ConversationPane.vue
index ffd288e56..db96b9c9b 100644
--- a/apps/kimi-web/src/components/ConversationPane.vue
+++ b/apps/kimi-web/src/components/ConversationPane.vue
@@ -78,6 +78,8 @@ const props = defineProps<{
   workspaceName?: string;
   /** Absolute workspace root path shown by the Open menu. */
   workspaceRoot?: string;
+  /** Git diff line stats for the header diff counter (mirrors kimi-cli/web). */
+  gitDiffStats?: { totalAdditions: number; totalDeletions: number } | null;
   /** Workspaces for the empty-composer picker (start a conversation elsewhere). */
   workspaces?: WorkspaceView[];
   /** Active workspace id, to highlight the current entry in the picker. */
@@ -685,6 +687,7 @@ onUnmounted(() => {
       :ahead="gitInfo?.ahead"
       :behind="gitInfo?.behind"
       :changes-count="changesCount"
+      :git-diff-stats="gitDiffStats"
       :is-git-repo="!!gitInfo"
       :pr="pr"
       :copied="copyConversationCopied"