This study evaluates the safety and efficiency of Pegylated Somatropin (PEG Somatropin) Injection in the treatment of endogenous growth hormone deficiency (GHD) in the broad population of children. Half of participants will receive the high dose, while the other half will receive the low dose.

Inclusion Criteria:

• Before starting treatment, according to the medical history, clinical symptoms and signs, GH stimulation test and imaging examination, patients are diagnosed as GHD.
• According to the height statistical data of Chinese children's physique development in nine cities in 2005, height is lower than the third percentile of growth curve of normal children with the same age and gender.
• Height velocity (HV) ≤5.0 cm/yr.
• GH stimulation test with two different mechanisms affirms that GH peak concentration of patients' plasma <10.0ng/ml.
• Bone age (BA) ≤9 years in girls and ≤10 years in boys, at least 1 year less than his/her chronological age (CA).
• Be in preadolescence (Tanner stage 1) and have a CA ≧ 3 years.
• Receive no prior GH treatment within 6 months.
• Sign informed consent.

Exclusion Criteria:

• People with abnormal liver or kidney function (ALT> 2 times the upper limit of normal value, Cr> the upper limit of normal value).
• Patients positive for hepatitis B core antigen (HBc), hepatitis B surface antigen (HBsAg) or hepatitis B e antigen (HBeAg).
• People with known highly allergic constitution or allergy to the drug of the study.
• People with severe cardiopulmonary, hematological and malignant tumors diseases or general infection and immune deficiency.
• Potential tumor patients (family history).
• Diabetic.
• Abnormal growth and development, such as Turner syndrome, constitutional delay of growth and puberty, Laron syndrome, growth hormone receptor deficiency, girls of growth retardation without excluding abnormal chromosome.
• Subjects took part in other clinical trial study within 3 months.
• Other conditions which in the opinion of the investigator preclude enrollment into the study.