The present study aimed at assessment of impact of Nuclear Power Plant site, Tarapur on macrobenthos diversity at seven locations, viz., TAPS 1&2, TAPS 3&4, Light house, Chinchani, Varor, Uchheli and Nandgoan for premonsoon, monsoon and postmonsoon seasons. Samples were collected for physico-chemical, hydro- sedimentological and macrobenthos study in intertidal area. The surface water temperature varied from 27.50C – 320C, whereas dissolved oxygen ranged from 6.2-7.5 mg l-1 and exceptionally low at Uchheli during monsoon season, i.e., 3.2 mg l-1. The sediment texture analysis indicated the dominance of sand > clay > silt at all locations and all seasons except in monsoon where it showed sand > silt > clay. 25 different groups of macrobenthos were identified among which polychaetes were most dominant and contributed numerically up to 74.3 % of total infaunal population. Shannon diversity index (H’) was observed maximum at TAPS 1& 2 (Premonsoon -2.88 and postmonsoon -3.00) and minimum at Uchheli (monsoon -1.03). Pearson’s correlation showed that dissolved oxygen positively correlated with Shannon-Weiner diversity H’ (p = 0.726), Pielous evenness J’ (p = 0.7511) and total species S with clay (p = 0.436). During present study, biodiversity of intertidal macrobenthos around Nuclear Power Plant site, Tarapur showed temporal and spatial variations.