diff --git a/datasette/cli.py b/datasette/cli.py
index 01423e7f0d..fb1fe7b95a 100644
--- a/datasette/cli.py
+++ b/datasette/cli.py
@@ -85,7 +85,7 @@ def sqlite_extensions(fn):
         "sqlite_extensions",
         "--load-extension",
         type=LoadExtension(),
-        envvar="SQLITE_EXTENSIONS",
+        envvar="DATASETTE_LOAD_EXTENSION",
         multiple=True,
         help="Path to a SQLite extension to load, and optional entrypoint",
     )(fn)