Nager syndrome is a rare malformation complex characterized by facial, limb, and skeletal morphogenesis. The mode of inheritance has not been definitely established. Major karyotypic abnormalities were seldom associated with this syndrome. We report on an infant with Nager acrofacial dysostosis that was associated with 45,X monosomy. This baby was born to a 36-year-old multigravid woman after 37 weeks of gestation and with maternal hydramnios. The baby girl died of airway obstruction due to retruded tongue 3 hours after birth. Phenotypically, this this patient had mandibulofacial dysostosis, radioulnar synostosis, hypoplasia and aplasia of thumbs, peripheral edema and apparently normal genital organs. We confirmed that major chromosomal anomaly including 45,X monosomy could be associated with Nager syndrome, although its pathogenetic significance remains unanswered.