Objective:To study the clinical features of children with Prader-Willi syndrome(PWS).Methods:Eighteen cases of PWS were collected from July 2016 to November 2018 in Shenzhen Maternal and Child Healthcare Hospital, Southern Medical University.The clinical data of children with PWS were analyzed retrospectively.Results:There were 12 males and 6 females in 18 cases with PWS.The diagnosis age ranged from 25 days to 9.5 years old [(3.09±3.02) years old]. Among them, 11 cases were in infancy (≤3 years old) and 7 cases after infancy (>3 years old). The main clinical features of infants with PWS were 11 cases of gonadal dysplasia (100.0%), 11 cases of psychomotor retardation (100.0%), 10 cases of hypotonia (90.1%), 6 cases of feeding difficulty and weak cry (54.5%). After infancy the main clinical features included 7 cases of psychomotor retardation (100.0%), 5 cases of hyperphagia(71.4%), 5 cases of obesity (71.4%), 5 cases of abnormal behavior problems (71.4%) and 4 cases of visual problems (57.1%). The clinical features of all patients throughout the developmental stage were as follows: decreased fetal movement, hypoplasia, neonatal hypotonia, weak cry, feeding difficulty, psychomotor delay, hyperphagia, obesity, abnormal behavior problems, and so on.Conclusions:The clinical features of PWS vary with age.The main clinical features in the infancy are hypotonia, weak cry, difficulty feeding and gonadal dysplasia.After infancy, there are hyperphagia, obesity, behavior and visual problems.And psychomotor retardation is present in the whole developmental stage of children with PWS.Early diagnosis and treatment are important for improving the prognosis of PWS.