Cerebro-Oculo-Nasal syndrome; a new multiple congenital anomaly/mental retardation syndrome was first reported by Richieri-Costa and Guion-Almeida in 1993 (Am J Med Genet 47:702-706) in two patients. To the best of our knowledge four additional cases have been reported. The main features of the syndrome are anophthalmia/microphthalmia, abnormal nares, and central nervous system anomalies. In this report, an additional sporadic case of this syndrome is presented. A 6-year-old girl from a non-consanguineous couple with normal prenatal growth parameters and retarded postnatal growth had anophthalmia, uplifted right nares with skin tag, and slight clefting at the tip of the nose, upper lip and gingiva. She also had a high-arched narrow palate, slightly low set ears, hypertelorism, a CNS defect and mental retardation. Additional findings were hypoplastic teeth with dental malocclusion, muscular hypotonia and midline hyperpigmentation over the anterior neck and the abdomen.