Abstract: Objective To elucidate the effects of micr owave irradiation on learning and memory function.Methods At different timepoints after microwave exposure of 65mW/cm² for 20min,learning and memory ability was evaluated with shuttle box test and Morris.water maze test,long-term potentiation(LTP)was detected in hippocampal slices in rats.Results After microwave exposure,the anus temperature increased more than 4℃,and average whole body SAR(specific absor ption rate)was 12.0 W/kg.At timepoints of 0 and 24 h after microwave irradiation,active avoidance response(AAR)decreased obviously than those before microwave irradiation(P<0.05).The latency of place,navigation was significantly increased at timepoints of 0 and 3 h after microwave irradiation(P<0.05),the times through platform and the time in target area were obviously decreased in spatial probetest in rats exposed to microwave compared with those in control rats(P<0.01).Significant obviously impaired induction of LTP in hippocampal slices were observed at timepoints of 0,12,24 h and 3 d after microwave irradiation(P<0.05).Conclusion Under the condition of this paper,microwave irradiation can result in learning and memory deficits in rats.Impaired induction of LTP in hippocampal slices is the electrophysiological basis of learning and memory deficits induced by microwave irradiation.