Secchi is a small lunar impact crater formation on the northwest edge of Mare Fecunditatis.

The western rim is joined with a section of the minor Montes Secchi range.

To the south is a pair of rilles designated the Rimae Secchi.

These lie near the edge of the mare, and have a combined length of about 40 kilometers.

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