A field experiment was conducted at G.B. Pant University of Agriculture & Technology, Pantnagar, Uttrakhand to evaluate the bio-efficacy of haloxyfop (10 EC), a post-emergence herbicide for weed control in soybean during kharif of 2007 and 2008. The experiment was conducted in randomized block design by taking eight treatments comprising, haloxyfop (10 EC) at 75, 100 and 125 g/ha, quizalofop 50 g/ha, fenoxaprop 100 g/ha, hand weeding (twice at 30 and 45 DAS), weed free and weedy. To evaluate the bio-efficacy of herbicides against grassy weeds, the broad leaf weeds were removed at 20 days after sowing of crop. The experimental field was mainly infested with Eleusine indica, Digitaria sanguinalis, Eragrostis japonica and Brachiaria species. Haloxyfop 100 g/ha was found effective when applied as post emergence to grassy weeds as compared to other treatments. This dose was found at par with haloxyfop 125 g/ha and better than Haloxyfop 75 g/ha. There was no phytotoxic effect on the crop due to haloxyfop. Untreated plot recorded 43 and 47% lower grain yield respectively in 2007 and 2008, as compared to weed free treatment. Application of fenoxaprop and quizalofop recorded comparable weed density with haloxyfop at 100 and 125 g/ha during the years.