The aim of the present study was to determine whether allogeneic red blood cell transfusions showed adeleterious effect and what might be preoperative risk factors for blood transfusion in patients with TNM stageII colon cancer. Total 470 patients who fulfilled inclusion criteria were selected for a further 10-year followupstudy. We found that there were statistical significance between non-transfused and transfused group inmortality (P=0.018), local recurrence (P=0.000) and distant metastasis (P=0.040). Local recurrence and distantmetastasis between 1 to 3 units and more than 3 units group did not show any significant differences. There wasno difference in survival rate between non-transfused and 1 to 3 units group (log rank =0.031, P=0.860). Thedifference between different blood transfusion volume in transfused patients was found (78.77% vs 63.83%,P=0.006). Meanwhile, the significant difference of survival rate was existed between non-transfused group andmore than 3 units group (84.83% vs 63.83%, P=0.002 ). Univariate analysis showed the following 3 variablesto be associated with an increased risk of allogeneic blood transfusions: preoperative CEA level (P<0.05),location of tumor (P<0.01) and diameter of tumor (P<0.01). Multivariate analysis revealed that location of tumorand diameter of tumor are two independent factors for requirement of perioperative transfusions. Therefore,allogeneic transfusion increase the postoperative tumor mortality, local recurrence and distant metastasis inpatients with stage II colon cancer. The postoperative tumor mortality, local recurrence and distant metastasiswere not associated with the blood transfusion volume. The blood transfusion volume was associated with thesurvival rate. Location of tumor and diameter of tumor were the independent preoperative risk factors for bloodtransfusion.