Abstract: An experiment on herbicidal weed control in mustard was conducted in two successive rabi seasons (1998-1999 and 1999-2000) to find out the effective herbicide for weed control in mustard. Performance of Ronstar and Setoff were tested against one hand weeding at 25 days after sowing and unweeded control plots using three mustard varieties (Daulat, Dhali and Tori-7). Application of Ronstar effectively reduced weed dry weight and gave 10 and 30% higher grain yield of mustard compared to hand weeding and unweeded control plots, respectively. Setoff also reduced weed dry weight but at the same time it reduced plant stand and yield attributes of mustard that causes 60-75% yield reduction compared to unweeded control plot. This indicates that Setoff is detrimental to weeds as well as mustard. Yield difference of the varieties was significant. Among the varieties, Daulat gave the highest grain yield. Interaction effect of varieties and weed control measures was significant. Across the seasons, Ronstar effectively reduced weed growth and consequently gave higher grain yield of mustard regardless of variety.