We report on a 3-1/2-year-old Spanish girl with the Neuhäuser megalocornea and mental retardation syndrome. A review shows that megalocornea, mental retardation, and, presumably, hypotonia, are the major manifestations for diagnosis. The facial appearance of the typical cases is characterised by frontal bossing, broad nasal bridge, mild hypertelorism, long upper lip, and small mandible.