Siedentopf is a worn impact crater on the far side of the Moon.

It lies to the east-southeast of the larger crater Vernadskiy.

The satellite crater Siedentopf Q intrudes into the rim along the southwestern side, and the rampart of this impact covers a portion of the interior floor of Siedentopf.

The remainder of the floor is marked by some small craterlets.

By convention these features are identified on lunar maps by placing the letter on the side of the crater midpoint that is closest to Siedentopf.