"Not Tonight" is the third single released from rapper Lil' Kim's debut album Hard Core and the first single she released after the death of The Notorious B.I.G. The version released as a single was the "Not Tonight (Remix)" (aka Ladies Night), which featured fellow female rappers Angie Martinez, Da Brat, Lisa "Left Eye" Lopes, and Missy Elliott. The music video was filmed in Miami, Florida and featured rapper Queen Latifah.

The single was a hit in the United States, reaching number-six on the Billboard Hot 100 and number-one on the Hot Rap Tracks chart. It peaked at number-eleven in the United Kingdom.