Chemical pesticides possess toxic and destructive impacts on the reproductive system and disrupt endocrine function. In this experimental study, the effect of movento, as a chemical pesticide, was investigated in comparison with chitosan, a biological pesticide, on the female reproductive system in vivo. In this study, 56 mice were randomly dived into 7 groups including control and experimental groups treated with movento and chitosan. After a 21-day treatment, mice were killed and their ovaries and blood being collected. In addition, the samples were fixed and stained with H & E method. The results exhibited that treatment with 2.5 and 5 mg/kg chitosan had no significant effect on the number and diameter of primary, secondary and antral follicles, while these items were significantly reduced in 10 mg/kg ch-itosan group and all movento-treated groups as well. In addition, the level of sexual hormones, such as estradiol, FSH and LH, was decreased in 10 mg/kg chitosan group and all movento-treated groups in comparison with the control gr-oup. The findings showed that movento affected the sexual hormone levels, ovary and ovarian follicle structure and in-duced abnormality in female reproductive system, while chitosan, as a biological pesticide, should be used due to its minimum effects on female reproductive system