An experiment was carried out at Kanour for two seasons, 1967-68 and 1968-69 to determine the comparative efflciency of some pre and post emergence her~icides sprayed in aqueous solution' b'y a knapsack sprayer, for the contra of weeds in potato var iety kufri shakti, Apal ic atlo n of Tok E-25 at the rate of 1.5 kg a. i./ha as pre-emergence treatment gave the highest tuber yield of potato (420.4 quintals/ha); this was followed by Stam F-34 (370.8) and Eotarn (330.4). Tok E-25, gave 39.1% higher tuber yield and when compared with control and other treatments the differences were significant. Weeds were controlled to the extent of 61.9% by Tok E-25. Eptarn as a pre-planting treatment, gave an overall 90.1% weed control and was found most effective in controlling Cyperus rotusulus, Stam F-34 showed only 42.8 percent control of the weeds.' Tok E-25 and Stam F-34 appeared promising and most economical herbicides for controlling weeds in potato. They not only gave signiflcantly higher yield, but also effectively controlled majority of the weeds. However, where Cyperus rotumdus is the problem, Eptam seems better. The highest income of Rs. 2936.00 per hectare was obtained with Tok E-25, followed by Starn F-34 (Rs. 2006.50) and Eptarn (Rs, 728.10)