Deepwater benthic algal collections were made by the research submersibles Johnson-Sea-Link I and Diaphus in the East Flower Garden Bank region of the Northwestern Gulf of Mexico during September of 1976, 1977, 1978, and 1980. Forty-one species were identified, 33 of which were new records for the Northwestern Gulf (Texas). Five species Halimeda gracilis, Titanophora incrustans, Compsothamnion thuyoides, Apoglossum ruscifolium, and Searlesia subtropica, are reported for the first time from the Gulf of Mexico.