The ammonite family Binneyitidae Reeside is represented in the Western Interior region of the United States by at least 3 species of Borissiakoceras, 5 species of Binneyites, and 1 species of a new genus, Johnsonites. The family is known only from the lower part of the Upper Cretaceous. Johnsonites, which is represented only by the genotype, occurs in the oldest of the Cenomanian zones of the Western Interior region. Borissiakoceras is found in the Cenomanian and in the lower part of the overlying Turonian. Binneyites has a range of about middle Turonian to lower Santonian. New species described are Johnsonites sulcatus, Borissiakoceras compressum, Binneyites carlilensis, B. nodosus, and B. rugosus.