We present a three-generation family with five retarded, abnormally appearing males and two abnormally appearing females (presumably manifesting carriers). The phenotype of the patients is different from that of all other previously described types of X-linked mental retardation (XLMR). The patients had prominent forehead, frontal bossing, hypertelorism, broad nasal tip, and anteverted nares. Chromosomes were normal including fragile X analysis. Skeletal roentgenograms were normal.