diff --git a/src/poetry/console/commands/build.py b/src/poetry/console/commands/build.py
index 3b2df69de4e..0de6728b37a 100644
--- a/src/poetry/console/commands/build.py
+++ b/src/poetry/console/commands/build.py
@@ -23,7 +23,7 @@ class BuildCommand(EnvCommand):
         option("format", "f", "Limit the format to either sdist or wheel.", flag=False),
         option(
             "clean",
-            "Clean output directory before building.",
+            description="Clean output directory before building.",
             flag=True,
         ),
         option(