Boca Chita Key Historic District, Historic district on Boca Chita Key, Florida, United States.

Boca Chita Key Historic District is a protected site on a small island within Biscayne National Park in Miami-Dade County, Florida. The grounds hold a lighthouse, a chapel, a pavilion, and several other limestone structures, all built in the late 1930s and forming a cohesive ensemble.

Mark C. Honeywell, an industrialist who owned the island, built its structures between 1937 and 1940 as a holiday resort, with the August Geiger firm as architects. After his wife's death his interest waned; he remarried and sold the island to Florence Emerman in 1942. The district was listed on the National Register of Historic Places on 1 August 1997.

The buildings on Boca Chita Key were built from local limestone in a style that was common among wealthy Florida estates in the 1930s. Walking through the grounds today gives a clear picture of how a private island retreat looked and felt when it was in active use.

The island can only be reached by boat, with departure points at marinas in and around Biscayne National Park. Visitors without their own boat can rent one or join a guided tour that covers the crossing.

The 65-foot lighthouse was built in 1938 to guide Honeywell's own boats, but it was shut down within hours of being lit because he had not informed the U.S. Coast Guard. The service treated the uncharted tower as a hazard to navigation, so it never served as an aid. Its windows were damaged by Hurricane Andrew in 1992.