the study aimed to follow up the effects of injection lead acetate into pregnant females on the testicular development and semen quality of their male births at puberty time. Forty mature female Swiss Webster mice (8-10) weeks old were divided into two equal groups (experimental and control). After mating with fertile males, the pregnant females injected intraperitoneally with 0.1 mg/kg of body weight of lead acetate from the first day of gestation and continued throughout the gestation period 20 days. While the control groups were injected by the same dose and rout of injection with normal saline. At parturition, numbers of the neonate were recorded. After six weeks the male births only isolated and weighted then mated with normal fertile females to evaluate their fertility through assessing their birth rate, then sacrificed to get their testes; each testis was weighted and the left one was fixed, then histological sections with a thickness of 5 microns were prepared. The epididymis was minced with warm normal saline to get a spermatozoal suspension to evaluate the sperm concentration, sperm motility, and abnormal sperm morphology and sperm viability. Results showed a highly significant decrease in the body and testicular weights of experimental male animals. A highly significant reduction in their birth rate after mating with normal partners was recorded together with a significant inverse changes in all semen parameters.