Dioscorea alata belongs to Dioscoreaceae or the yam family. Around 600 Dioscorea species are consumed in various regions of the world. Dioscorea alata is well known cultivated tuber consumed by both rural and urban people. In this study, we have investigated the nutrient composition, phytochemicals, and antioxidant and antimicrobial activity of the underground and aerial tubers of Dioscorea alata. The result of the analysis showed that the aerial tuber of D. alata contained a higher amount of moisture (68.51%), ash (4.64%), starch (5.61%), reducing sugar (0.029%), fat (0.33%) and protein (1.39%) than underground tuber of D. alata. At the same time, carbohydrates, free amino acids, vitamin C, sodium, potassium and iron contents were superior in the underground tuber than in the aerial tuber. Further, both underground and aerial tuber was a good source of phenols, flavonoids, tannins and diosgenin. The underground tuber exhibited better DPPH scavenging potential compared to the aerial tuber. Six solvents extract of D. alata showed significant to moderate antibacterial activity toward seven tested clinical stains. Thus, the tuber of D. alata could be used as a better food supplement to meet the calorie requirement and a rich source of relevant antimicrobial agents to treat microbial infections.