短吻鳄科（学名：Alligatoridae）也称鼍科，为爬行纲鳄目的一科，因吻部短而宽，故名。现仅存4属8种。

The family Alligatoridae of crocodylians includes alligators and caimans.

The lineage including alligators proper (Alligatorinae) occurs in the fluvial deposits of the age of the Upper Chalk in Europe, where they did not die out until the Pliocene age. The true alligators are today represented by two species, A. mississippiensis in the southeastern United States, which can grow to 15 ft (4.6 m) and weigh 1000 lbs (453 kg) and the small A. sinensis in the Yangtze River, China, which grows to an average of 5 ft (1.5 m). Their name derives from the Spanish el lagarto, which means "the lizard".