A male infant with partial monosomy 10 q and partial trisomy 11q as a result of de novo unbalanced translocation between the long arms of chromosomes 10 and 11: der(10)t(10;11)(q26;q13) is described. He had craniofacial dysmorphy, congenital heart defects, urogenital and cerebral anomalies, and severe developmental delay. To the best of our knowledge, this is the first report of this combination of chromosomal abnormalities.