FU Jun-fen will report the clinical trial of daily GH treatment in children with idiopathic short stature (ISS). This study aimed to evaluate the efficacy and safety of daily GH treatment, as well as to determine the optimal dose of Jintropin® AQ in ISS children. Prepubertal children from 11 hospitals who were diagnosed as ISS were enrolled in this phase III study. Eligible patients were randomized 2:1 into the study group (Jintropin® AQ 0.05 mg/kg/d, n=362) and the control group (no intervention, n=119) for 52 weeks. The primary endpoint was the change of height standard deviation score (HT-SDS) from baseline. The results showed that Jintropin® AQ at a dose of 0.05mg/kg/d was effective and showed great safety profiles in ISS treatment. There was a significantly greater improvement in growth parameters in the 0.05mg/kg/d group compared to untreated subjects. Further extension phase will evaluate the long-term efficacy and safety of Jintropin AQ treatment in ISS.