It has been revealed that excessive fluoride intake on long-term is associated with toxic effects and can damage a variety of organs and tissues in the human body, including the male reproductive system. However, the molecular mechanisms of fluoride-induced male reproductive toxicity are not well understood. The study wants to get news concerning the effects of natrium fluoride on testicular tissues when this substance is administrated to a population of mice. The study was conducted on NMRI mice descending from the pregnant females treated with 0.25 mg and 0.5 mg natrium fluoride by daily gavage, from the beginning of pregnancy until the lactation is ceased. Then, the mice, males and females, were divided in six groups, three groups descending from the pregnant females treated with 0.5 mg natrium fluoride (Groups A, B and C) and three groups from the pregnant females with 0.25 mg natrium fluoride (Groups D, E and F). From the moment when the lactation is finished until the adulthood, the animals received the following treatments: homeopathic (a CH7 solution of natrium fluoride – Groups A and D), allopathic-homeopathic (0.25 mg‰ natrium fluoride administered like drinking water ad libitum and CH7 solution of natrium fluoride – Group E; 0.5 mg‰ natrium fluoride administered like drinking water ad libitum and CH7 solution of natrium fluoride – Group B), and allopathic administration of natrium fluoride (0.25 mg‰ natrium fluoride like drinking water ad libitum – Group F; 0.5 mg‰ natrium fluoride like drinking water ad libitum – Group C). When the males reached the adulthood, the administration of natrium fluoride was stopped and, by randomization, they where selected for euthanasia. The euthanasia was realized by cervical dislocation. The testes for the histopathological examination were preserved in a 10% formalin solution. The preparation of samples for optical microscopy was realized with Hematoxylin-Eosin staining. The results indicate that natrium fluoride administered in different doses, even at homeopathic dose or at allopathic-homeopathic dose, determined vacuolar dystrophy of epididymal epithelial cells, vacuolar dystrophy of linear seminal cells and necrosis.