diff --git a/src/claude_agent_sdk/_internal/transport/subprocess_cli.py b/src/claude_agent_sdk/_internal/transport/subprocess_cli.py
index faaec2d5..4911e4d2 100644
--- a/src/claude_agent_sdk/_internal/transport/subprocess_cli.py
+++ b/src/claude_agent_sdk/_internal/transport/subprocess_cli.py
@@ -317,7 +317,7 @@ def _build_command(self) -> list[str]:
         if effective_allowed_tools:
             cmd.extend(["--allowedTools", ",".join(effective_allowed_tools)])
 
-        if self._options.max_turns:
+        if self._options.max_turns is not None:
             cmd.extend(["--max-turns", str(self._options.max_turns)])
 
         if self._options.max_budget_usd is not None: