diff --git a/config/base-kimi.settings.json b/config/base-kimi.settings.json
index 5ad236f9..ad4b2dee 100644
--- a/config/base-kimi.settings.json
+++ b/config/base-kimi.settings.json
@@ -1,7 +1,11 @@
 {
   "env": {
     "ANTHROPIC_BASE_URL": "https://api.kimi.com/coding/",
-    "ANTHROPIC_AUTH_TOKEN": "YOUR_KIMI_API_KEY_HERE"
+    "ANTHROPIC_AUTH_TOKEN": "YOUR_KIMI_API_KEY_HERE",
+    "ANTHROPIC_MODEL": "kimi-k2-thinking-turbo",
+    "ANTHROPIC_DEFAULT_OPUS_MODEL": "kimi-k2-thinking-turbo",
+    "ANTHROPIC_DEFAULT_SONNET_MODEL": "kimi-k2-thinking-turbo",
+    "ANTHROPIC_DEFAULT_HAIKU_MODEL": "kimi-k2-thinking-turbo"
   },
   "alwaysThinkingEnabled": true
 }
\ No newline at end of file
diff --git a/installers/install.sh b/installers/install.sh
index e9c3fbc8..a2dd1187 100755
--- a/installers/install.sh
+++ b/installers/install.sh
@@ -62,7 +62,7 @@ INSTALL_DIR="${INSTALL_DIR:-$HOME/.local/bin}"
 CCS_DIR="$HOME/.ccs"
 CLAUDE_DIR="$HOME/.claude"
 GLM_MODEL="glm-4.6"
-KIMI_MODEL="kimi-for-coding"
+KIMI_MODEL="kimi-k2-thinking-turbo"
 
 # Resolve script directory (handles both file-based and piped execution)
 if [[ -n "${BASH_SOURCE[0]:-}" ]]; then
diff --git a/scripts/postinstall.js b/scripts/postinstall.js
index 4db3256b..07c2862a 100755
--- a/scripts/postinstall.js
+++ b/scripts/postinstall.js
@@ -336,7 +336,11 @@ function createConfigFiles() {
       const kimiSettings = {
         env: {
           ANTHROPIC_BASE_URL: 'https://api.kimi.com/coding/',
-          ANTHROPIC_AUTH_TOKEN: 'YOUR_KIMI_API_KEY_HERE'
+          ANTHROPIC_AUTH_TOKEN: 'YOUR_KIMI_API_KEY_HERE',
+          ANTHROPIC_MODEL: 'kimi-k2-thinking-turbo',
+          ANTHROPIC_DEFAULT_OPUS_MODEL: 'kimi-k2-thinking-turbo',
+          ANTHROPIC_DEFAULT_SONNET_MODEL: 'kimi-k2-thinking-turbo',
+          ANTHROPIC_DEFAULT_HAIKU_MODEL: 'kimi-k2-thinking-turbo'
         },
         alwaysThinkingEnabled: true
       };
@@ -360,12 +364,13 @@ function createConfigFiles() {
     // They are created on-demand when user runs `ccs gemini` or `ccs codex` for the first time
     // This prevents confusion - users need to run `--auth` first anyway
 
-    // Migrate existing Kimi configs to remove deprecated model fields (v4.1.2)
-    // Kimi API changed - model fields now cause 401 errors
+    // Migrate existing Kimi configs to use kimi-k2-thinking-turbo model (v5.5.0)
+    // Kimi API now supports model specification with thinking models
     if (fs.existsSync(kimiSettingsPath)) {
       try {
         const existing = JSON.parse(fs.readFileSync(kimiSettingsPath, 'utf8'));
         let updated = false;
+        const defaultModel = 'kimi-k2-thinking-turbo';
 
         // Ensure env object exists
         if (!existing.env) {
@@ -373,22 +378,27 @@ function createConfigFiles() {
           updated = true;
         }
 
-        // Remove deprecated model fields that cause 401 errors
-        const deprecatedFields = [
-          'ANTHROPIC_MODEL',
-          'ANTHROPIC_SMALL_FAST_MODEL',
-          'ANTHROPIC_DEFAULT_OPUS_MODEL',
-          'ANTHROPIC_DEFAULT_SONNET_MODEL',
-          'ANTHROPIC_DEFAULT_HAIKU_MODEL'
-        ];
+        // Add/update model fields to use kimi-k2-thinking-turbo
+        const modelFields = {
+          ANTHROPIC_MODEL: defaultModel,
+          ANTHROPIC_DEFAULT_OPUS_MODEL: defaultModel,
+          ANTHROPIC_DEFAULT_SONNET_MODEL: defaultModel,
+          ANTHROPIC_DEFAULT_HAIKU_MODEL: defaultModel
+        };
 
-        for (const field of deprecatedFields) {
-          if (existing.env[field] !== undefined) {
-            delete existing.env[field];
+        for (const [field, value] of Object.entries(modelFields)) {
+          if (existing.env[field] !== value) {
+            existing.env[field] = value;
             updated = true;
           }
         }
 
+        // Remove deprecated ANTHROPIC_SMALL_FAST_MODEL if present
+        if (existing.env.ANTHROPIC_SMALL_FAST_MODEL !== undefined) {
+          delete existing.env.ANTHROPIC_SMALL_FAST_MODEL;
+          updated = true;
+        }
+
         // Ensure required fields exist
         if (!existing.env.ANTHROPIC_BASE_URL) {
           existing.env.ANTHROPIC_BASE_URL = 'https://api.kimi.com/coding/';
@@ -406,13 +416,11 @@ function createConfigFiles() {
           const tmpPath = `${kimiSettingsPath}.tmp`;
           fs.writeFileSync(tmpPath, JSON.stringify(existing, null, 2) + '\n', 'utf8');
           fs.renameSync(tmpPath, kimiSettingsPath);
-          console.log('[OK] Migrated Kimi config (v4.1.2): removed deprecated model fields');
-          console.log('     Kimi API no longer requires model fields (they cause 401 errors)');
+          console.log('[OK] Migrated Kimi config (v5.5.0): updated to kimi-k2-thinking-turbo model');
         }
       } catch (err) {
         console.warn('[!] Kimi config migration failed:', err.message);
-        console.warn('    Existing config preserved, but may cause 401 errors');
-        console.warn('    Manually remove ANTHROPIC_MODEL fields from ~/.ccs/kimi.settings.json');
+        console.warn('    Existing config preserved');
       }
     }