diff --git a/docs/runner.rst b/docs/runner.rst
index 6d687f88..d2e2d77c 100644
--- a/docs/runner.rst
+++ b/docs/runner.rst
@@ -170,7 +170,7 @@ Common options:
 
     Default: ``1``
 
-``--trusted_proxy_headers=LIST``
+``--trusted-proxy-headers=LIST``
     Which of the proxy headers should we trust, this is a set where you
     either specify "forwarded" or one or more of "x-forwarded-host", "x-forwarded-for",
     "x-forwarded-proto", "x-forwarded-port", "x-forwarded-by".
diff --git a/src/waitress/runner.py b/src/waitress/runner.py
index 90f42970..020bb50a 100644
--- a/src/waitress/runner.py
+++ b/src/waitress/runner.py
@@ -148,7 +148,7 @@
 
         Default: 1
 
-    --trusted_proxy_headers=LIST
+    --trusted-proxy-headers=LIST
         Which of the proxy headers should we trust, this is a set where you
         either specify "forwarded" or one or more of "x-forwarded-host",
         "x-forwarded-for", "x-forwarded-proto", "x-forwarded-port",