diff --git a/studio/backend/core/inference/providers.py b/studio/backend/core/inference/providers.py
index 90d83bc441..654d9672c1 100644
--- a/studio/backend/core/inference/providers.py
+++ b/studio/backend/core/inference/providers.py
@@ -140,6 +140,20 @@ PROVIDER_REGISTRY: dict[str, dict[str, Any]] = {
         "openai_compatible": False,
         "notes": "Native Anthropic Messages API. Uses x-api-key header and /v1/messages endpoint with SSE translation.",
     },
+    "deepseek": {
+        "display_name": "DeepSeek",
+        "base_url": "https://api.deepseek.com/v1",
+        "default_models": [
+            "deepseek-chat",
+            "deepseek-reasoner",
+        ],
+        "supports_streaming": True,
+        "supports_vision": False,
+        "supports_tool_calling": True,
+        "auth_header": "Authorization",
+        "auth_prefix": "Bearer ",
+        "notes": "OpenAI-compatible API. deepseek-chat = V3, deepseek-reasoner = R1 thinking mode.",
+    },
     "openrouter": {
         "display_name": "OpenRouter",
         "base_url": "https://openrouter.ai/api/v1",
diff --git a/studio/backend/tests/test_providers_api.py b/studio/backend/tests/test_providers_api.py
index 93bd363c92..9482c14c69 100644
--- a/studio/backend/tests/test_providers_api.py
+++ b/studio/backend/tests/test_providers_api.py
@@ -49,7 +49,8 @@ _PROVIDER_CONFIGS: dict[str, tuple[str, str]] = {
     "fireworks":  ("FIREWORKS_API_KEY", "accounts/fireworks/models/llama4-maverick-instruct-basic"),
     "perplexity": ("PERPLEXITY_API_KEY", "sonar"),
     "openrouter": ("OPENROUTER_API_KEY", "openai/gpt-4o-mini"),
-    "anthropic": ("ANTHROPIC_API_KEY",  "claude-haiku-4-5"),
+    "anthropic":  ("ANTHROPIC_API_KEY",  "claude-haiku-4-5"),
+    "deepseek":   ("DEEPSEEK_API_KEY",   "deepseek-chat"),
 }
 
 PROVIDER_KEYS: dict[str, str] = {
@@ -241,7 +242,7 @@ class TestRegistry:
         )
         assert resp.status_code == 200, f"Registry failed: {resp.text}"
         providers = resp.json()
-        assert len(providers) == 9, f"Expected 9 providers, got {len(providers)}: {providers}"
+        assert len(providers) == 10, f"Expected 10 providers, got {len(providers)}: {providers}"
         print(f"\n  {'Provider':<12} {'Base URL'}")
         print(f"  {'-'*12} {'-'*45}")
         for p in providers: