Weed infestation is one of the major threats to crop growth and yield.Weed control is the method of limiting weed infestation so that crops can be grown profitably. Metsulfuron methyl + Chlorimuron ethyl is a new post-emergence herbicide in Bangladesh. Field trials were conducted at Bangladesh Rice Research Institute (BRRI), Gazipur during Aman, 2014 and Boro, 2014-15 to evaluate the efficacy of Metsulfuron methyl 10% + Chlorimuron ethyl 2% WP on weed suppression and performance of transplanted rice. Metsulfuron methyl 10% + Chlorimuron ethyl 2% WP @ 15, 20 and 25 g ha-1 were applied and Pyrazosulfuran ethyl @ 125 g ha-1, weed free and unweeded control were used for comparison. Visual observation indicated that this herbicide possesses high selectivity and not toxic to rice plants. The results revealed that the major weed flora associated with the transplanted rice was mainly comprised of two grasses, two sedges and three broadleaves in Aman, 2014 and two grasses, two sedge and two broad leaves in Boro, 2014-15. The most dominant weeds were Cyperus difformis, Echinochloa crus-galli, Scirpus maritimus and Monochoria vaginalis in both the growing seasons. Application of Metsulfuron methyl 10% + Chlorimuron ethyl 2% WP @ 20 g ha-1 was most effective to suppress weed density and dry masses in both the seasons resulting increased grain yield more than 30% as compared to unweeded control. Therefore, Metsulfuron methyl 10% + Chlorimuron ethyl 2% WP @ 20 g ha-1 should apply at one to two leaf stage of weed may be recommended for effectively control weed in transplanted rice.