This study evaluated the effectiveness of recombinant human interleukin-11 (rhIL-11) in the treatment of immune thrombocytopenia (ITP) and determined whether clinical and laboratory findings predicted the treatment response.This retrospective, single-center, case-control study included 103 adult patients with ITP treated between July 2010 and April 2014 at Jiangxi Province People's Hospital. About 49 patients in the pred+IL group received prednisone (conventional dose) combined with an rhIL-11 regimen, and 54 patients in the pred alone group received prednisone (conventional dose) alone. Demographic data, initial and follow-up platelet counts, proportions of patients achieving platelet counts ≥30 × 10/L (response) and ≥100 × 10/L (complete response) at different time points, and adverse reactions were compared between groups.Complete response rates were similar between groups overall but higher in the pred+IL group than in the pred alone group for newly diagnosed patients and those with severe ITP (P < .05). Proportions of patients achieving response or complete response at different time points were similar between groups overall but higher in the pred+IL group than in the pred alone group for newly diagnosed patients and those with severe ITP (P < .05). Posttreatment platelet count correlated negatively with platelet count at diagnosis and white blood cell (WBC) count at diagnosis in patients with newly diagnosed ITP (r = -0.337, P = .073 and r = -0.367, P = .050, respectively) or ITP with bleeding-related episodes (r = -0.357, P = .020 and r = -0.434, P = .004, respectively). No immediate or postinfusion severe adverse reactions were observed.rhIL-11 increased CR and improved hemostasis in patients with newly diagnosed or severe ITP. Platelet and WBC counts at diagnosis can predict the response to rhIL-11.