The study was evaluated as the optimal dose for the treatment of SGA short stature children by Pegylated Somatropin, initially evaluated its efficiency and safety for the treatment of SGA short stature children and provided scientific, reliable basis for phase III clinical trials for dose selection. This is a multicenter, randomized, open-label, dose-response trial, including a 52-week main phase and an ongoing safety extension phase continuing until reaching near-adult height (NAH) in China. Ninety-six growth hormone (GH)-treatment-naïve, non-GH-deficient, prepubertal short children born SGA were randomized in a 1:1 ration to receive weekly subcutaneous administration of Jintrolong 0.1 mg/kg/week or 0.2 mg/kg/week for 52 weeks. Children who completed the 52- week main phase proceeded to the extension phase, while Jintrolong was administered at an initial dose of 0.2 mg/kg/week. Dose adjustments based on annualized height velocity (AHV) and insulin-like growth factor I (IGF-I) response, were made up to a maximum of 0.4 mg/kg/week until achieved NAH or the patient's voluntary discontinuation.