Arsenic contamination is a serious issue throughout the world and is substantial risk factor in most of the countries including India. Chronic arsenic exposure from drinking water to humans is causing major public health related issues. The present study aims to investigate the ameliorative effect of Citrullus lanatus (Watermelon) seeds against arsenic induced reproductive function and testicular toxicity in Charles Foster rats. In the present study, twenty-four male Charles Foster rats (120±5gm). The study group includes group -I (n=6) as control, and group -II (n=18) treated with sodium arsenite (8 mg per Kg body weight per day) for 90 days. The group -II was furthermore divided into three sub-groups, Group -II-a, Group -II-b and Group -II-c. The group -II-a were sacrificed to see the effect of arsenic toxicity effect after arsenic exposure. Group -II-b was left with normal food and water for next 60 days to observe auto recovery. The group -II-c rats were administered with Citrullus lanatus (Watermelon) hydroxyl ethanolic seeds extract at the dose of 400 mg per Kg body weight per day for 60 days for 90 days upon pre-treated sodium arsenite treated group (8 mg per kg body weight). After completion of the experiment, all the treated group of animals were sacrificed for biochemical, hormonal assay, histopathological, testicular and reproductive functions study. In the arsenic treated rats' group, there was significant (p<0.001) changes in serum levels of SGPT, SGOT, urea, uric acid and creatinine as well as in haematological parameters. There was decrease in the sperm counts and sperm motility accompanied by an increased incidence of sperm abnormalities and hormonal imbalance denotes infertility condition. In contrast, after the administration with C.lanatus (Watermelon) seeds hydroxy-ethanolic extract upon arsenic treated rats group, there was significant (p<0.001) improvement observed in the reproductive, hepatic and renal parameters. In the arsenic intoxicant rats' group, after administration with C. lanatus (Watermelon) seeds hydroxyl ethanolic extract, there was significant (p<001) reduction in the arsenic concentration in blood, liver, and kidney tissues as well as serum lipid peroxidation. The histopathological study also showed the C. lanatus (Watermelon) seeds hydroxy ethanolic extract significantly restored the cellular integrity of testicular cells leading to normal functioning of it against arsenic induced toxicity.