Abstarct: This study was carried out in order to investigate drought tolerance and competitive ability of wheat genotypes with weeds in rainfed and supplemental irrigation condition in two locations (Shirvan Rainfed Agricultural Research Station and Sisab Agricultural Research station) in North Khorasan Province in 2015-2016. The experiment was conducted as split plot (weed control methods as main factors and wheat genotypes as sub factors) in a randomized complete block design with 20 advanced dryland wheat genotypes in four replications in two conditions of rainfed and supplemental irrigation. The results showed that, supplemental irrigation increased significantly most of growth and yield traits in different wheat genotypes than rainfed conditions in two regions. baxsed on combined analysis of variance, number of spike per square meter, number of grain per spike, 1000-seed weight and grain yield were significantly increased in Sisab than Shirvan region. The results showed that 17 and 12 genotypes with 2780 and 2608 kg/ha grain yield under supplemental irrigation (without stress) and with 2263 and 2119 kg/ha grain yield under stress conditions, were superior to other genotypes. Fernandez drought tolerance index, mean productivity and geometric mean index of yield with 0.95, 0.93 and 0.82 had the most correlation with wheat grain yield respectively. The results showed that weeds density and dry biomass was greater in supplementary irrigation than rainfed conditions in both regions of study. Also, in Sisab region the density and dry matter of weeds was increased than Shirvan region significantly. The amount of weed damage on grain yield of different genotypes of wheat under supplementary irrigation conditions was higher than rainfed conditions significantly. baxsed on the results, 12 and 17 genotypes had the highest grain yield in both irrigation and rain fed conditions in weed and weed free treatments compared to other genotypes. The highest reduction in weed biomass was observed in competition with 12 and 17 genotypes, and the weed damage in both supplementary irrigation and rain-fed conditions was lower in genotypes 12 and 17 than other genotypes. According to the results of this experiment, genotypes 12 and 17 were better than other genotypes in terms of growth and yield and competition with weeds under supplemental irrigation and rain fed conditions.