A field experiment was conducted during 2013-14, 2014-15 and 2015-16 at ICAR-Central Potato Research Station, Shillong to evaluate the bio-efficacy of weed management practices in rainfed potato under North-Eastern hill region of India. Maximum potato tubers yield (21.3 t/ha) was recorded under weed free treatment followed by metribuzin application 0.75 kg/ha as a pre-emergence (PE). Reduction in crop yield due to presence of weeds was 54.0 per cent. Maximum uptake of nutrients, viz. nitrogen (113.2 kg/ha), phosphorus (14.5      kg/ha) and potassium (89.4 kg/ha) were recorded by the potato under weed free fb application of metribuzin 0.75 kg/ha as a PE. The highest net returns                       ( 176100/ha) and B:C ratio (2.3) were recorded under the metribuzin application 0.75 kg/ha. Thus, application of metribuzin 0.75 kg/ha as PE was found more effective in potato under the rainfed ecosystem of North-Eastern hill region of India.