Penicillin on Wax is the debut studio album by American New York-based rapper Tim Dog. It was released on November 12, 1991, via Ruffhouse Records. The album was produced by Tim Dog, Ced-Gee, TR Love and Moe Love from Ultramagnetic MC's, Bobby Crawford, and Louis Flores. Kool Keith made uncredited guest appearances on two tracks.

The album spawned three singles, the infamous underground hit "Fuck Compton" (which disses the N.W.A.), "Step to Me" and "Bronx Nigga". The album peaked at number 155 on the US Billboard 200 chart, number 34 on the Top R&B/Hip-Hop Albums chart, number 4 on the Heatseekers Albums chart.