A field study was conducted during 2009 at Raipur in an inceptisol with rainy season rice to evaluate the effect of herbicides application on biochemical characteristics of rhizosphere soil under different tillage systems. Four different types of tillage system were evaluated viz. (i) conventional-conventional (ii) conventional-zero (iii) zero-conventional and (iv) zero-zero. Among weed control measures, comparative effects of hand weeding and recommended herbicides application (butachlor as pre-emergence and fenoxaprop-p-ethyl + ethoxysulfuron as post-emergence herbicide 1.5 kg, 56.25 g and 15 g/ha, respectively) were tested compared with a weedy check (control). The conventional-conventional tillage system was found most effective to improve the biochemical characteristics of soil. Under this system, maximum organic C content was accumulated in rhizosphere soil and also found maximum enzyme activity (dehydrogenase activity, acidic phosphatase activity and alkaline phosphatase activity). Application of pre- and post- emergence herbicide reduced the biochemical activities in soil after its application (3 and 22 days after sowing, respectively) to 35 days of sowing of the crop thereafter it became normalize due to degradation of applied herbicides.