Background: Insecticides are chemicals that are often encountered in everyday life. These substances can disrupt the body's endocrine hormonal balance so that it's called Endocrine Disrupting Chemicals (EDCs). EDC works by disrupting the hypothalamic-pituitary-testicular axis. Thus, it can affect the Leydig cell.Aim: To determine the effect of exposure of estrogen-containing insecticides to testicular Leydig cell histological appearance.Methods: This was a true experimental study with parallel post-test only control group design. It used Sprague Dawley rat aged 3 days post-natal (n = 25) which were randomlydivided into 5 groups (control group (n = 5); 25 mg β estradiol 3-benzoate (n = 5); burning mosquito repellent (n = 5); 3 ml of liquid mosquito repellent (n = 5); and 4 ml of liquid mosquito repellent (n = 5)). Exposure is given for 28 days. At the age of 100 days, testes were taken and examined their histopathological appearance of Leydig cell Malignancies using HE staining. The statistical test used Kruskal-Wallis and Mann-Whitney test.Results: In this study, there was an increase in the number of testicular Leydig cell groups in each treatment group as compared tocontrol group. There was significant difference between control group with 25 mg β estradiol 3-benzoate (p = 0.007), burning mosquito repellent (p = 0.008), and liquid repellent 4 ml (p = 0.008) treated group. However, there was no significant difference between the treatment groups of 3 ml liquid repellent as compraed to the control group (p = 0.827).Conclusion: Exposure to insecticides may lead to increase in the number of Leydig cell groups.