Medicinal properties of plants make them potent to prevent or cure diseases. Cassia occidentalis Linn. is an important member of plant family Leguminaceae commonly known as kasundi in hindi, coffee senna in English. Hexane, acetone and aqueous extracts of the plant of Cassia occidentalis were investigated for antibacterial activity against Escherichia coli, Klebsiella pneumonia, Proteus mirabilis, Pseudomonas aeruginosa and Staphylococcus aureus. The maximum zone of inhibition was observed in Proteus mirabilis in Acetone extract and minimum zone of inhibition was observed in Pseudomonas aeruginosa in aqueous extract.