Objective To evaluate the inhibitory effect of Sisheng decoction on the hippocampal neuron injury induced by electromagnetic radiation in rats. Methods Rats were irradiated with electromagnetic radiation sources for 4 weeks, with low-, medium-, and high-dose radiation power densities of 10, 20, and 40 mW/cm², respectively. The Morris water maze was used to evaluate the effect of Sisheng decoction on the learning and memory decline caused by electromagnetic radiation in rats, with physiological saline as the blank control and anduolin capsule as the positive control. TUNEL kit and flow cytometry were used to detect the level of apoptosis in hippocampal neurons of rats with electromagnetic radiation injury, and reactive oxygen species (ROS) kit and flow cytometry were used to detect the ROS content in hippocampal neurons of rats. Results The results of the Morris water maze test showed that on the 7^th day after high-dose radiation, the average escape latency (AEL) of the rats in the blank control group was significantly longer than that in the Sisheng decoction group and anduolin group, and the AEL of the rats in the anduolin group was significantly longer than that in the Sisheng decoction group (all P＜0.05). On the 3^rd day after medium-dose radiation, the AEL of the rats in the blank control group was significantly longer than that in the Sisheng decoction group and anduolin group (both P＜0.05); on the 14^th and 28^th days, the AEL of the rats in the blank control group and anduolin group was significantly longer than that in the Sisheng decoction group (all P＜0.05). After exposed to low-dose radiation, there was no significant difference in AEL between the blank control group and the Sisheng decoction or anduolin groups (both P＞0.05). The apoptosis test result confirmed that the apoptosis rates of hippocampal neurons in rats exposed to high- and medium-dose radiation were significantly higher than that exposed to low-dose radiation (both P＜0.05). After exposed to high-, medium-, and low-dose radiation, the neuronal apoptosis rates of the rats in the anduolin group and Sisheng decoction group were significantly lower than those in the blank control group (all P＜0.05). After exposed to high-dose radiation, the apoptosis rate of neurons of the rats in the Sisheng decoction group was significantly lower than that in the anduolin group (P＜0.05). There were no significant differences in ROS contents in hippocampal neurons among rats under high-, medium-, or low-dose radiation (P＞0.05). However, the ROS contents in neurons of the anduolin group and Sisheng decoction group were significantly lower than that in the blank control group (both P＜0.05). After exposed to medium-dose radiation, the ROS inhibition effect of the Sisheng decoction group was stronger than that in the anduolin group (P＜0.05). Conclusion Sisheng decoction can inhibit the apoptosis of hippocampal neurons in rats, reduce the ROS content in their cells, and alleviate the injury to learning and memory caused by electromagnetic radiation in rats.