Background: The pesticide’s broad-spectrum nature raises concerns about its impact on biodiversity, potentially disrupting delicate ecological balances and endangering various species across different trophic levels. Deltamethrin, a widely used synthetic pyrethroid, poses significant risks to both the environment and animals. Its persistence in soil and water can lead to the contamination of ecosystems, affecting non-target insects, aquatic life, and birds.Methods: This study aims to detect the impact of deltamethrin on the testicular tissues of white rabbits treated by 0.1 and 0.3 mg/kg/day for 30 days. Thirty rabbits were divided into three groups equally. The first group was the control group and was administered distilled water, while the second group experimental groups 1 and 2 received deltamethrin at a concentration of 0.1 and 0.3 mg/kg/day respectively. Tissue sections were prepared, stained and tested via a light microscope equipped with a camera.Result: The results obtained revealed that all groups of animals treated with deltamethrin experienced disintegration in the germinal cell layer, detachment of the germinal epithelium from the basal membrane, and slight distortion in spermatozoa. The damage was more severe with increasing the concentration, Moreover, there was an increase in the contraction of some seminiferous tubules, resulting in their irregular and wavy appearance, and many cellular changes were observed, in addition to absence of spermatozoa in some seminiferous tubule lumina and Leydig cell hyperplasia.Conclusion: The treatment with deltamethrin at different doses for one month caused severe pathological tissue damage in the testes, characterized by congestion, hemorrhage, vacuolation, and detachment of a portion of the germinal epithelium from the basement membrane
