In this study， Lactobacillus casei Zhang（LCZ） was used as the research object. Twenty male SD rats were randomly divided into two groups： the control group （NC group） and the LCZ group （4×109 CFU/mL/d）. The effect of LCZ on spatial learning and memory of rats was evaluated by the time（escape latency） of adult rats to reach the target hole during the Barnes maze test. The results showed that during the training of spatial learning for 4 days the escape latency of rats in the LCZ group was shorter than that in the NC group gradually， and a significant difference appeared on the 3rd day （95.63 s±86.78 s， P<0.05）；The escape latency of LCZ group rats was （93.65±71.88） s， which was significantly shorter than that of NC group （174.42±77.51） s during the test of short-term spatial memeory （P<0.05）. In summary， LCZ can significantly improve the spatial learning and memory of rats.