Partial trisomy 3p results from either unbalanced translocation or de novo duplication. Common clinical features consist of dysmorphic facial features, congenital heart defects, psychomotor and mental retardation, abnormal muscle tone and hypoplastic genitalia. In this paper, we report a case of partial trisomy 3p with rare clinical manifestations. A full-term, female newborn was admitted to our hospital with complaints of repeated seizures and developmental retardation. On evaluation chromosome 3p duplication was detected.