Ｏｂｊｅｃｔｉｖｅ　Discuss the influence of BIS monitoring on the incidence of postoperative delirium(POD) in elderly patients with chronic anemia.　Methods　One hundred and eighty cases of elective surgery under general anesthesia were randomly divided into BIS monitoring group and control group(n=90), the control group using routine anesthesia, and BIS monitoring group maintaining the value of BIS between 40-60 during anesthesia. The hemodynamic indexes were monitored after entering the operation room(T0), after anesthesia(T1), immediate intubation(T2), 3 min after intubation(T3), cut the skin(T4), 1 h during operation(T5), the end of operation(T6). Observe the dose of propofol during anesthesia, surgery time, extubation time, recovery time and the occurrence of POD in patients.　Results　The overall incidence of BIS monitoring group delirium was 17.5%, lower than 31.2% in the control group(P<0.05), the incidence of delirium on the first day of 13.3% was significantly lower than 28.9% in the control group(P<0.05), the incidence of 5.6% in the second day also lower than 14.4% in the control group(P<0.05), and duration of delirium was significantly lower than the control group (P<0.05). The extubation time[(26±8) min] and hospital stays[(11.5±2.3) d] of BIS monitoring group were significantly earlier than[(41±12) min and (12.6±4.4) d] control group， the difference was statistically significant(P<0.05).　Conclusions　BIS monitored anesthesia reduces the incidence of POD and reduces the duration of delirium in elderly patients with chronic anemia.