A new pre-emergence herbicide, clomazone+2,4-DEE, was evaluated for the control of mixed weed flora in transplanted rice. In general, bleached and white colour seedlings of Echinochloa were emerged under c1omazone+2,4-DEE treated plots, later on which were completely dead. In both the years, presence of broadleaf weeds was negligible. In general, per cent control of Echinochloa was significantly higher (90 to 95%) under all the grassy herbicides tested than the weedy plots in the year 2003. It was recorded that weed density and dry weight were significantly lower and were at par among all the doses of clomazone +2,4-DEE, butachlor at 1500 g ha" and aniJofos at 400 g ha-'. Increase in number of tillers was observed in all herbicide treatments over weedy check. The number of tillers and grain yield of paddy obtained under clomazone+2,4-DEE at 1500 g ha" in 2002 and under all the clomazone+2,4-DEE doses tested during the year 2003, were significantly higher over weedy plot and were at par with the yield obtained with the application of butachlor, anilofos and with weed-free treatments. The difference in the performance of c1omazone+2,4-D between the two years study was due to the drought effect in the year 2002 when submergence could not be maintained in the experimental field. Hence, it is concluded that clomazone+2,4-DEE mixture is very effective against Echinochloa in transplanted rice provided submergence is maintained atleast for 15-20 days after the appl ication of herbicide treatment.