Objective To understand the change of erythrocyte immunity and matondialdehyde (MDA) in perioperative patients with mammary cancer. Methods30 patients were divided randomly into two groups:group A(general anesthesia) and group B(epidural block). To estimate the activity of erythrocyte complement receptor I (CR- I ) and the lever of MDA, the venous blood were collected at the time points of before anesthesia, after anesthesia, during operation, and on the 1st, the 3rd, the 5th postoperative day. ResrltsCompared with before anesthesia, the RBCC3bRR, RBCCaR and RFER in group A were decreased statistically at the time points of after anesthesia, during operation, and on the 1st, the 3rd postoperative day(P ＜0.05 or P ＜0.01). Above mentioned index in group B were reduced significantly only during operation and on the 1st postoperative day. Between two groups, above mentioned index in group A were lower than those in group B(P＜0.05).Compared with before anesthesia, RFIR and MDA in group A were higher at the time points of after anesthesia, during operation, and on the 1st, the 3rd postoperative day(P＜0.05 or P＜0.01).but above mentioned index in group B rose only on the 1st postoperative day.CR- I and MDA in two groups restored to the lever of be fore anesthesia on the 5th postoperative day. ConclusionThe perioperative immunological function of erythrocyte is obviously depressed by general anesthesia and epidural block, especially the former. This depression is relevant to the disorder of erythrocyte immunity regulating function and the lever of plasma MDA.