Pistia stratiotes belongs to family Araceae. Pistia stratiotes leaves are traditionally used against ringworm infection of scalp, boils and syphilitic eruptions. Traditionally, oil extracts of Pistia stratiotes are used for treatment of tuberculosis, asthma and dysentery. As the effect of Pistia stratiotes extracts on the area of cytotoxicity is unexplored, the present work was aimed at evaluating the effect of extracts on cancer cell line and also on clinical pathogens. Phytochemical study was done with methanol extract of Pistia stratiotes leaves. Analytical study (GC-MS and TLC) was done with methanol, chloroform and hexane extracts of Pistia stratiotes leaves. Antimicrobial activity by well diffusion method and antioxidant activity by DPPH assay were also done. Antimicrobial study was done against eight clinical pathogens namely, Proteus mirabilis, Enterococcus sp., Salmonella sp., Shigella sp., Staphylococcus aureus, Serretia sp., Klebsiella sp., Pseudomonas aeuroginosa. As bone cancer is an aggressive form of cancer MG63 cell line of osteocarcoma was choosen for the study. © 2014 Jayanthi Abraham et al, publisher and licensee IYPF.