The prospective study included congenital cataract (CC) patients ≤ 18 years old and firstly present to the ZOC in Guangzhou from 2011 to 2017. The included patients registered in the CC database after being diagnosed as CC by at least two experienced pediatric ophthalmologists based on the slit-lamp and Pentacam examinations. The detailed basic information of each CC patient including the demography, family heredity, gestation history, complicated systemic disease, living condition and the family environment were investigated to parents by a structured questionnaire and were recorded in the CC database. The healthy children without CC were set as control. More than 1000 subjects should be included in each group.