Medicinal plants are being used as traditional medicines to cure several infectious and non-infectious diseases because of their products are safe in contrast to the synthetic medicines that are considered as unsafe to human including other animals and environment. We selected Solanum nigrum L. (Makoi) which belongs to family Solanaceae to evaluate antimicrobial activities against six pathogenic bacteria Staphylococcus aureus, Bacillus cereus, Escherichia coli, Salmonella typhimurium, Pseudomonas aeroginosa and Enterobacter aerogens. Phytochemical analysis of the plant (crude extract of leaves, fruits and stems) showed the presence saponins, tannins, alkaloids, terpenoides, flavonoides and steroids etc. The extract of leaves, fruits and stemsprepared using five different solvents (hexane, chloroform, acetone, ethanol and water) showed antimicrobial activates against all selected pathogenic bacteria. But water extract of leaves, acetone extract of fruits and hexane extract of stems showed maximum zone of inhibition such as21.30±1.50, 16.67±0.58 and 14.30±1.52 respectively against Pseudomonas aeroginosa. Thus, we can say that S. nigrum possess broad spectrum antimicrobial activities against several pathogenic bacteria and can be used clinically to find novel antibacterial compounds for various diseases.