Introduction: The number of neurons in the hippocampus can have a direct effect on its function. The plant Brazembel from the mint family may have antioxidant properties. The aim of the present study was to investigate the effects of stress and Brazmble extract on neuronal density of CA1, CA2 in male rats. Methods: In this experimental study, Wistar rats were divided into 6 groups (n=5), including control, and negative control under stress, also experimental group,including stress and get Brazmbl doses of the extract mL 50, mL 75 and mL 100. Limiting stress for 21 days, the rats were exposed in 2 hours. Groups receiving the extract for 21 days, to get inside limiting extracts were gavaged. After removal of the brain by perfusion, the hippocampus was excised and stained, and the neuronal density was calculated by dissector and metasteriology. The results were analyzed by Minitab 16 software with t-test and ANOVA at a significant level (P