Purpose: To determine the intraocular pressure (lOP) in Chinese children and to investigate the possible relationship between intraocular pressure and other ocular biometric factors.Methods: Twins aged 8 to 16 years were recruited from Guangzhou Twin Registry.lOP was estimated with Tono-pen tonometer.Central corneal thickness and corneal radius of curvature was measured using rotating Scheimpflug camera (Pentacam Oculus, Wetzlar, Germany).The right eyes were chosen to assess the relationship between lOP and its relating factors.Generalized Estimating Equations (GEE model) was used adjust for the similarities of twin pairs.