The unicellular un-branched filamentous fresh water alga Mougeotia (C. A. Agardh) is interesting due to its vigorous and luxuriant growth in its habitat throughout the year. The present study was undertaken to investigate the antimicrobial tests to ascertain the presence of such compounds that help in widespread distribution of the alga throughout the year and its dominance over other fresh water algal organisms. Antimicrobial test shows the algal extract were more potent against bacteria viz. gram +ve bacteria Staphylococcus aureus and gram -ve bacteria Escherichia coli as compared to two human pathogenic fungi Candida albicans and Asprgillus niger.