Background: Bisphenol A is a xenoestrogen, synthesized in large quantities for the production of polymers (polycarbonates, epoxy resins) and thermal paper, and is widely used in products of everyday use (packaging, containers and bottles). Data concerning the occurrence of BPA in food, water and indoor environments as well as its appearance in tissues and body fluids of the human body are available in the literature. Male accessory sex glands are also vulnerable to environmental endocrine disruptors with adverse effects in adulthood. The developing prostate gland is particularly sensitive to estrogens and high-dose exposures during a critical developmental window results in intraepithelial prostatic neoplasia (PIN) in adult rodent models. Bisphenol A is also an endocrine disruptor. High levels of BPA exposure correlate with increased risk of mammary gland, brain and prostate cancers and have adverse effects on the tissues of the prostate and seminal vesicles. Objectives: The aim of this study was to investigate the effects of BPA doses on the histological structure and ultrastructure of prostate and seminal vesicle glands. Methods: Forty male Wistar rats were randomly divided into four groups (n = 10): A control group and three treatment groups,