Donkey punch is a slang term for an apocryphal and potentially lethal sexual practice supposedly performed during anal sex. The purported practice involves the penetrating partner punching the receiving partner in the back of the head or neck (what is known in boxing as a rabbit punch, after a technique to kill rabbits) allegedly causing the receiving partner's anal passage to tense up and increase the pleasure of the penetrating partner. When used, the donkey punch is almost exclusively executed during or just before the orgasm of the penetrating partner.

There is some controversy concerning whether the initial sexual act is restricted to anal sex prior to the donkey punch, or whether muscular contraction after the blow to the back of the head or neck during vaginal sex can also qualify as a donkey punch. It has even been proposed that a possible use of the donkey punch is to create a situation in which there can be a "surprise anal penetration" tantamount to sexual assault or rape.