diff --git a/web-app/src/containers/dialogs/AddModel.tsx b/web-app/src/containers/dialogs/AddModel.tsx
index 2b87fb222..e8fd4e0fd 100644
--- a/web-app/src/containers/dialogs/AddModel.tsx
+++ b/web-app/src/containers/dialogs/AddModel.tsx
@@ -17,6 +17,7 @@ import { getProviderTitle } from '@/lib/utils'
 import { useTranslation } from '@/i18n/react-i18next-compat'
 import { ModelCapabilities } from '@/types/models'
 import { models as providerModels } from 'token.js'
+import { toast } from 'sonner'
 
 type DialogAddModelProps = {
   provider: ModelProvider
@@ -37,8 +38,13 @@ export const DialogAddModel = ({ provider, trigger }: DialogAddModelProps) => {
 
   // Handle form submission
   const handleSubmit = () => {
-    if (!modelId.trim()) {
-      return // Don't submit if model ID is empty
+    if (!modelId.trim()) return // Don't submit if model ID is empty
+
+    if (provider.models.some((e) => e.id === modelId)) {
+      toast.error(t('providers:addModel.modelExists'), {
+        description: t('providers:addModel.modelExistsDesc'),
+      })
+      return // Don't submit if model ID already exists
     }
 
     // Create the new model
diff --git a/web-app/src/locales/de-DE/providers.json b/web-app/src/locales/de-DE/providers.json
index 7e6d68c0f..39c52e047 100644
--- a/web-app/src/locales/de-DE/providers.json
+++ b/web-app/src/locales/de-DE/providers.json
@@ -35,7 +35,9 @@
     "modelId": "Modell ID",
     "enterModelId": "Modell ID eingeben",
     "exploreModels": "Sehe Modellliste von {{provider}}",
-    "addModel": "Modell hinzufügen"
+    "addModel": "Modell hinzufügen",
+    "modelExists": "Modell bereits vorhanden",
+    "modelExistsDesc": "Bitte wähle eine andere Modell-ID."
   },
   "deleteModel": {
     "title": "Lösche Modell: {{modelId}}",
diff --git a/web-app/src/locales/en/providers.json b/web-app/src/locales/en/providers.json
index 62fe69b8e..2683432f9 100644
--- a/web-app/src/locales/en/providers.json
+++ b/web-app/src/locales/en/providers.json
@@ -35,7 +35,9 @@
     "modelId": "Model ID",
     "enterModelId": "Enter model ID",
     "exploreModels": "See model list from {{provider}}",
-    "addModel": "Add Model"
+    "addModel": "Add Model",
+    "modelExists": "Model already exists",
+    "modelExistsDesc": "Please choose a different model ID."
   },
   "deleteModel": {
     "title": "Delete Model: {{modelId}}",
@@ -69,4 +71,4 @@
   "addProvider": "Add Provider",
   "addOpenAIProvider": "Add OpenAI Provider",
   "enterNameForProvider": "Enter name for provider"
-}
\ No newline at end of file
+}
diff --git a/web-app/src/locales/id/providers.json b/web-app/src/locales/id/providers.json
index 803aac3e7..5f89d69c6 100644
--- a/web-app/src/locales/id/providers.json
+++ b/web-app/src/locales/id/providers.json
@@ -35,7 +35,9 @@
     "modelId": "ID Model",
     "enterModelId": "Masukkan ID model",
     "exploreModels": "Lihat daftar model dari {{provider}}",
-    "addModel": "Tambah Model"
+    "addModel": "Tambah Model",
+    "modelExists": "Model sudah ada",
+    "modelExistsDesc": "Silakan pilih ID model yang berbeda."
   },
   "deleteModel": {
     "title": "Hapus Model: {{modelId}}",
@@ -69,4 +71,4 @@
   "addProvider": "Tambah Penyedia",
   "addOpenAIProvider": "Tambah Penyedia OpenAI",
   "enterNameForProvider": "Masukkan nama untuk penyedia"
-}
\ No newline at end of file
+}
diff --git a/web-app/src/locales/pl/providers.json b/web-app/src/locales/pl/providers.json
index 55992e3bb..c1c03434e 100644
--- a/web-app/src/locales/pl/providers.json
+++ b/web-app/src/locales/pl/providers.json
@@ -35,7 +35,9 @@
     "modelId": "Identyfikator Modelu",
     "enterModelId": "Wprowadź identyfikator modelu",
     "exploreModels": "Zobacz listę modeli dostawcy {{provider}}",
-    "addModel": "Dodaj Model"
+    "addModel": "Dodaj Model",
+    "modelExists": "Model już istnieje",
+    "modelExistsDesc": "Wybierz inny identyfikator modelu."
   },
   "deleteModel": {
     "title": "Usuń Model: {{modelId}}",
diff --git a/web-app/src/locales/vn/providers.json b/web-app/src/locales/vn/providers.json
index bd6bdb334..8c0e6d1b8 100644
--- a/web-app/src/locales/vn/providers.json
+++ b/web-app/src/locales/vn/providers.json
@@ -35,7 +35,9 @@
     "modelId": "ID mô hình",
     "enterModelId": "Nhập ID mô hình",
     "exploreModels": "Xem danh sách mô hình từ {{provider}}",
-    "addModel": "Thêm mô hình"
+    "addModel": "Thêm mô hình",
+    "modelExists": "Mô hình đã tồn tại",
+    "modelExistsDesc": "Vui lòng chọn một ID mô hình khác."
   },
   "deleteModel": {
     "title": "Xóa mô hình: {{modelId}}",
@@ -69,4 +71,4 @@
   "addProvider": "Thêm nhà cung cấp",
   "addOpenAIProvider": "Thêm nhà cung cấp OpenAI",
   "enterNameForProvider": "Nhập tên cho nhà cung cấp"
-}
\ No newline at end of file
+}
diff --git a/web-app/src/locales/zh-CN/providers.json b/web-app/src/locales/zh-CN/providers.json
index ecc04df49..2ca2beb2e 100644
--- a/web-app/src/locales/zh-CN/providers.json
+++ b/web-app/src/locales/zh-CN/providers.json
@@ -35,7 +35,9 @@
     "modelId": "模型 ID",
     "enterModelId": "输入模型 ID",
     "exploreModels": "查看 {{provider}} 的模型列表",
-    "addModel": "添加模型"
+    "addModel": "添加模型",
+    "modelExists": "模型已存在",
+    "modelExistsDesc": "请选择不同的模型 ID。"
   },
   "deleteModel": {
     "title": "删除模型：{{modelId}}",
@@ -69,4 +71,4 @@
   "addProvider": "添加提供商",
   "addOpenAIProvider": "添加 OpenAI 提供商",
   "enterNameForProvider": "输入提供商名称"
-}
\ No newline at end of file
+}
diff --git a/web-app/src/locales/zh-TW/providers.json b/web-app/src/locales/zh-TW/providers.json
index 316a9ed08..39580818b 100644
--- a/web-app/src/locales/zh-TW/providers.json
+++ b/web-app/src/locales/zh-TW/providers.json
@@ -35,7 +35,9 @@
     "modelId": "模型 ID",
     "enterModelId": "輸入模型 ID",
     "exploreModels": "查看 {{provider}} 的模型清單",
-    "addModel": "新增模型"
+    "addModel": "新增模型",
+    "modelExists": "模型已存在",
+    "modelExistsDesc": "請選擇不同的模型 ID。"
   },
   "deleteModel": {
     "title": "刪除模型：{{modelId}}",
@@ -69,4 +71,4 @@
   "addProvider": "新增提供者",
   "addOpenAIProvider": "新增 OpenAI 提供者",
   "enterNameForProvider": "輸入提供者名稱"
-}
\ No newline at end of file
+}