This research article published by Academic Journals, Vol. 16(4), 2022Black seeds from papaya plants are utilized as traditional medicine in African and Asian cultures to improve the functioning of the male reproductive system and management of prostate cancer. This study analyzed the phytochemical composition, antiproliferative activity and cytotoxicity of Carica papaya black seeds against the prostate cancer cells and Vero cells. Phytochemical screening was performed by standard procedures. Methyl tetrazolium bromide (MTT) cell viability assay was used to evaluate the antiproliferative effect of crude extracts in prostate cancer cells against the control. Phytocompounds, namely flavonoids, alkaloids, tannins, terpenoids, glycosides and saponins were found in the crude extracts. All papaya seeds’ extracts had antiproliferative activity towards prostate cancer cells. Ethyl acetate extract was found with higher antiproliferative activity with IC50 of 3.64 µg/ml. The crude extracts were not toxic towards Vero cells as compared to the control. Isolation and characterization of active compounds from herein crude extracts and papaya black seeds are therefore recommended for future studies.