Allium cepa (onion) belongs to the family Liliaceae and found mainly in temperate region. Due to its significant medicinal properties, nutritional worth, and energy value, Allium cepa (onion) imparts numerous health benefits to users. This study was conducted to investigate the phytochemical, mineral and vitamin composition of Allium cepa (onion) peels. The phytochemical screening revealed that the peels contained moderate amount of alkaloids (29.4%), and flavonoid (16.1%). Phenol was present in minute quantity of 0.64% and saponin content was appreciable (8.5%). However, tannin was absent. The phytochemical screening also revealed the presence of ANTI nutrients such as oxalate and phytate in minute quantities of 2.64% and 0.17% respectively. However, hydrogen cyanide was absent. The minerals screened for were Ca, Mg, Fe and P, and the result showed that the plant was riches in Ca (12.65%), followed by Mg (1.24%), while the other two were more or less absent. The vitamin analysis revealed the plant has extremely low vitamin contents of A and C. The result of the analysis, having shown onion is a good carrier of Phytochemicals such as alkaloid, flavonoids, saponins, and minerals such as Ca, and Mg, concludes that onion peel can contribute appreciably to human health as an antimicrobial as well as an alternative source of nutritional supplements in as much as it suggests further investigation for other nutritional components of the plant part.