Background & Objective: Amygdal is a subcortical nucleus of limbic system that has a pivotal role in behavioral, vegetative and endocrine activities. Sexual dimporphism in some amygdale nuclei have been investigated. The aim of this study was to answer this query: does the total volume of amygdale nucleus differ in two sex morphometrically? Material & Methods: This study was conducted on Adult wistar rats (male and female N=10 per group, 8weeks old, weight 240-260 gr). Brains were removed and fixed in formalin 10% and in 10 µm sections were prepared by microtome. After staining with cresyl violet 1% the boundary of amygdal was defined and its volume calculated with cavalieri method Results: The volume of amygdala nucleus was estimated 2.07 ± 0.12mm3 in male rats and 1.57± 0.11 mm3 in female rats (P<0.05). Conclusion: Based on our finding the total volume of amygdala nucleus in male rats is larger than those of female rats that suggest the sexual dimorphism of amygdala nucleus between tow genders .These findings may have implications for developmental studies dimorphisms in human amygdala.