The present study was performed for the period of one year from June 2012 to May 2013 in order to understand the level of toxic heavy metals in the sediments of Mahim Creek near Mumbai. The annual average concentration of heavy metals like Pb, Cd, Cr, Zn, Cu, Ni and Hg was found to be 9.88, 2.33, 1.41, 33.31, 22.07, 32.21 and 32.06 ppm respectively. It is feared that this heavy metals accumulated in the creek sediments might affect the benthic macro invertebrates whose metabolic activities contribute to aquatic productivity. The results of present study indicates that the existing situation if mishandled can cause toxic effect on sediment dwelling organisms and fish, resulting in decrease survival, reduced growth, or impaired reproduction and lowered species diversity.