The antimicrobial activity of Sida cordifolia leaf extracts (aqueous and methanolic) on pathogenic bacteria (Staphylococcus aureus, Enterococcus fecalis, Pseudomonas aeruginosa, and Proteus mirabilis) and fungi (Candida albicans and Cryptococcus neoformans) was tested by disc diffusion method. The aqueous extract was found to be moderately effective against bacteria and exhibited high antifungal activity at a concentration of 2mg/disc. The methanolic extract was effective on bacteria and did not show any antifungal activity. Acetone fraction did not contain any antimicrobial activity. Increasing concentrations of the extracts (aqueous and methanolic) exhibited increased zone of inhibition against the bacteria and fungi (7-20mm). Our results suggest that aqueous extracts of Sida cordifolia leaves show high antimicrobial activity and contains phytochemicals that are responsible for such an activity. Further analysis of the extracts to isolate and identify the phytochemicals from Sida cordifolia will be helpful to test the therapeutic potential and industrial applications.