Perdido Key, Florida is an unincorporated community located in Escambia County, Florida, between Pensacola, Florida and Orange Beach, Alabama. "Perdido" means "lost" in the Spanish language, and Perdido Key is sometimes called "Lost Key" by local residents and businesses.

The community is located on Perdido Key, a barrier island located in extreme northwest Florida and southeast Alabama. The Florida district of the Gulf Islands National Seashore is located at the east end of the island. No more than a few hundred yards wide in most places, Perdido Key stretches some 16 miles from Perdido Pass Bridge near Orange Beach, Alabama, to just across from Santa Rosa Island near Pensacola, Florida.