This study attempts to characterize the clinical features of various subtypes of juvenile idiopathic arthritis (JIA) and try to investigate the prognostic factors. Patients with JIA hospitalized in Nanjing Children Hospital during April 2005 to April 2010 were enrolled. Clinical manifestations and laboratory parameters were retrospectively reviewed. A total of 202 cases were included, 105 males and 97 females, with average age at onset of 7.5 years. Patients with systemic JIA were most common, accounting for 47.0%. Fever, rash, and arthritis were the most common clinical manifestations. The most commonly involved joints were the knee and ankle. Laboratory parameters were significantly different but not specific. Time from onset to treatment, hepatomegaly, and involvement of wrist may have a significant effect on the outcome. A total of 117 cases were followed up, with an average follow-up time of 2 years. Among them, 55 cases achieved complete remission, 27 cases with partial remission, and 29 cases without remission, and six died. JIA is a heterogeneous disease with varied onset and clinical manifestations, which makes treatment a serious challenge. Receiving treatment late, hepatomegaly, and impaired wrist were early risk factors for an unfavorable outcome.