Costello syndrome is a rare, distinctive, multiple congenital anomaly syndrome, characterized by soft, loose skin with deep palmar and plantar creases, loose joints, distinctive coarse facial features and skeletal and cardiac abnormalities. The affected patients have a predisposition to develop malignancy, developmental delays and mental retardation. Recently, a 7-year-old male child born to normal nonconsanguineous parents presented to us with abnormal facial features, arrhythmia, mitral valve dysfunction and growth retardation. His cutaneous examination revealed lax and pigmented skin over hands and feet with deep creases, acanthosis nigricans and short curly hairs. Its differentiation from other syndromes with similar clinical features is discussed in this article.