Abstract: Objective　To analyze the outcome of childhood B-cell acute lymphoblastic leukemia treated(ALL) with SCMC-ALL-2005 protocol. Methods Newly diagnosed B-cell ALL from May 1, 2005 to April 30, 2009 in five hospitals were treated and followed up according to SCMC-ALL-2005 protocol. Results A total of 601 cases with newly diagnosed B-cell ALL were enrolled. Among them, 539 cases (89.68%) were followed up until September 30, 2011. In 601 patients, there were 284 low-risk cases (LR group), 231 moderate-risk cases (MR group) and 86 high-risk cases (HR group) which were treated with SCMC-ALL-2005 protocol. The total complete remission rate during the period of induction was 98.84% and 7 cases did not achieve complete remission. The median time of the first event occurring was 35 months (2.94 years). Among 539 cases completing follow-up, 403 cases (74.77%) completed treatment including 223 cases (86.43%) in LR group, 150 cases (73.17%) in MR group and 30 cases (39.47%) in HR group. The rate of cases completing treatment was significantly different among three groups (P=0.001). The completion rate was highest in LR group and lowest in HR group. The 3-year overall survival (OS) rate was (83.3±1.8) %, and the 3-year EFS (event-free survival) rate was (79.2±1.9) % using a Kaplan-Meier method. The 5-year OS rate was (79.5±3.3) %, and the 5-year EFS rate was (70.9±3.7) %. There were significant differences in 3-year EFS rate and 5-year EFS rate among three groups (P<0.05). Conclusions Childhood B-ALL treated with SCMC-ALL-2005 protocol achieved a better therapeutic effect and prognosis. The multi-center collaborative research is useful for the standard treatment of ALL.