diff --git a/Dockerfile b/Dockerfile
index 5bc76281..a18077f0 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -26,6 +26,7 @@ ENV PORT="80"
 ENV MODEL_REVISION=""
 ENV MODEL_CACHE_DIR="/models"
 ENV MODEL_LOAD_IN_8BIT="false"
+ENV MODEL_LOAD_IN_4BIT="false"
 ENV MODEL_LOCAL_FILES_ONLY="false"
 ENV MODEL_TRUST_REMOTE_CODE="false"
 ENV MODEL_HALF_PRECISION="false"
diff --git a/basaran/__init__.py b/basaran/__init__.py
index 28281577..28f20bd3 100644
--- a/basaran/__init__.py
+++ b/basaran/__init__.py
@@ -21,6 +21,7 @@ def is_true(value):
 MODEL_REVISION = os.getenv("MODEL_REVISION", "")
 MODEL_CACHE_DIR = os.getenv("MODEL_CACHE_DIR", "models")
 MODEL_LOAD_IN_8BIT = is_true(os.getenv("MODEL_LOAD_IN_8BIT", ""))
+MODEL_LOAD_IN_4BIT = is_true(os.getenv("MODEL_LOAD_IN_4BIT", ""))
 MODEL_LOCAL_FILES_ONLY = is_true(os.getenv("MODEL_LOCAL_FILES_ONLY", ""))
 MODEL_TRUST_REMOTE_CODE = is_true(os.getenv("MODEL_TRUST_REMOTE_CODE", ""))
 MODEL_HALF_PRECISION = is_true(os.getenv("MODEL_HALF_PRECISION", ""))
diff --git a/basaran/__main__.py b/basaran/__main__.py
index 570d48a3..bcd123b2 100644
--- a/basaran/__main__.py
+++ b/basaran/__main__.py
@@ -20,6 +20,7 @@
 from . import MODEL_REVISION
 from . import MODEL_CACHE_DIR
 from . import MODEL_LOAD_IN_8BIT
+from . import MODEL_LOAD_IN_4BIT
 from . import MODEL_LOCAL_FILES_ONLY
 from . import MODEL_TRUST_REMOTE_CODE
 from . import MODEL_HALF_PRECISION
@@ -42,6 +43,7 @@
     revision=MODEL_REVISION,
     cache_dir=MODEL_CACHE_DIR,
     load_in_8bit=MODEL_LOAD_IN_8BIT,
+    load_in_4bit=MODEL_LOAD_IN_4BIT,
     local_files_only=MODEL_LOCAL_FILES_ONLY,
     trust_remote_code=MODEL_TRUST_REMOTE_CODE,
     half_precision=MODEL_HALF_PRECISION,
diff --git a/basaran/model.py b/basaran/model.py
index b681cf30..f5d35406 100644
--- a/basaran/model.py
+++ b/basaran/model.py
@@ -302,6 +302,7 @@ def load_model(
     revision=None,
     cache_dir=None,
     load_in_8bit=False,
+    load_in_4bit=False,
     local_files_only=False,
     trust_remote_code=False,
     half_precision=False,
@@ -322,9 +323,10 @@ def load_model(
         kwargs = kwargs.copy()
         kwargs["device_map"] = "auto"
         kwargs["load_in_8bit"] = load_in_8bit
+        kwargs["load_in_4bit"] = load_in_4bit
 
         # Cast all parameters to float16 if quantization is enabled.
-        if half_precision or load_in_8bit:
+        if half_precision or load_in_8bit or load_in_4bit:
             kwargs["torch_dtype"] = torch.float16
 
     # Support both decoder-only and encoder-decoder models.