Abstract: Present study assayed the toxicity effect of ethanolic leaf and seed extract of Cassia alata and found promising activity. From the probit transformation of resulting mortality data we got LC50 values of 4.31 ppm (μg mL-1) for seed and 5.29 ppm for leaf extract. Seed extract explored potent cytotoxicity similar to the standard gallic acid (LC50 = 4.53 ppm). From the antibacterial and MIC data it was evident that seed extract gave least activity against the tested bacteria whereas leaf extract deserved promising antibacterial activity.