Objective:To gain insight into the constitution of juvenile rheumatic diseases, treatment outcome and trends of rheumatic inpatients in past 12 years, and to improve awareness of juvenile rheumatic diseases.Methods:The clinical data of 5 950 patients in rheumatology department of the affiliated pediatric hospital of Fudan University (from 2005 to 2016) were analyzed retrospectively, and the chi-square test was used to compare and analyze the incidence.Results:Disease changes: ① The top three rheumatic diseases were Kawasaki disease (KD) (44.3%), Henoch-schoniein purpura (HSP) (35.4%), juvenile idiopathic arthritis (JIA)(9.6%). ② The number of all constitution of juvenile rheumatic diseases in hospital increased other than HSP. ③ The rheumatic diseases were increased from 17 to 37 kinds in the past 6 years. ④ The number of systemic lupus erythematosus (SLE) increased year by year (112/2 348 vs 197/3 602, χ2=1.41, P=0.235), as well as the severe SLE (35/112 vs 55/197, χ2=0.38, P=0.536). ⑤ The rate of rheumatic diseases complicated with macrophage activation (MAS) was 7.2‰(43/5 950). 12.9%(26/201) of systemic juvenile idiopathic arthritis(sJIA) were complicated with MAS, which was accounted for 60.5%(26/43) of total number of MAS in rheumatic diseases. In the last 6 years, there was a significant increase in the number of patients with MAS in patients with rheumatic diseases ( χ2=14.1, P<0.01) and sJIA( χ2=11.2, P<0.01). ⑥ 1.1%(64/5 950) of rheumatic diseases patients had lung lesions, juvenile dermatomyositis (JDM) accounted for 24.4%(20/82). In the last 6 years, the number of patients with lung lesions associated with rheumatic diseases increased significantly ( χ2=5.66, P=0.017). ⑦ The mortality rate of juvenile rheumatic diseases was only 3.7‰(22/5 950), and 45.5% occurred in SLE (10/22). The mortality rate of SLE decreased in last 6 years (5/112 vs 5/197, χ2=0.34, P=0.558). Conclusion:The constitution of juvenile rheumatic diseases in our center is decreasing for systemic vasculitis (KD, HSP), JIA, SLE, JDM in last 6 years. The annual total number of patients is relatively stable. But rare, difficult and critically illed cases increase year by year. Although SLE is still the primary cause of death in juvenile rheumatic diseases in recent 6 years, the mortality rate has decreased year by year.