Citrullus lanatus is medicinal plants believed to have many agents acting in different ways for the health benefits of human. This study investigated the acute phytochemical contents and effect of the methanol extract on weight changes, relative organ weight, hematological parameters and biomarkers of prostate dysfunction. The result indicated the presence of alkaloids, terpenes, flavonoids, Reducing sugar, tannins and phenols. Acute toxicity studies showed that the extract was safe at 5000mg/kgbwt. All the animals recorded increase in body weight and the relative organ weight showed significant increase (p