diff --git a/aider/main.py b/aider/main.py
index ea1c31a5d..17a2121c2 100644
--- a/aider/main.py
+++ b/aider/main.py
@@ -454,17 +454,6 @@ def main(argv=None, input=None, output=None, force_git_root=None, return_coder=F
     # Load the .env file specified in the arguments
     loaded_dotenvs = load_dotenv_files(git_root, args.env_file, args.encoding)
 
-    # Process any environment variables set via --set-env
-    if args.set_env:
-        for env_setting in args.set_env:
-            try:
-                name, value = env_setting.split("=", 1)
-                os.environ[name.strip()] = value.strip()
-            except ValueError:
-                io.tool_error(f"Invalid --set-env format: {env_setting}")
-                io.tool_output("Format should be: ENV_VAR_NAME=value")
-                return 1
-
     # Parse again to include any arguments that might have been defined in .env
     args = parser.parse_args(argv)