Potocki-Shaffer syndrome (PSS) results from deletion of proximal short arm of chromosome 11. We present a 14-month-old male baby with cardinal pictures of PSS such as bilateral parietal foraminae, abnormal craniofacial appearance, hypotonia and developmental delay. Cytogenetic study revealed deletion of chromosome 11 from p11.12 to p11.2 in this proband and his mother, but microsatellite marker study showed deletion only in this proband. Despite previous negative chromosome study, positive family history with two similarly affected elder siblings and the finding of bilateral parietal foraminae finally lead to the etiologic diagnosis.