A field experiment was conducted at the Agricultural Research Farm, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi, in the rainy (kharif) season to study the bio- efficacy of various early post-emergence (EPoE) herbicides against weeds in cotton. The experiment consisted of eleven treatments (including the one only for phytotoxicity studies), replicated three times, and laid out in a randomized block design. The various treatments that were incurred in this experimental study were pyrithiobac-sodium 7.5%+ haloxyfop-R-methyl 13.5% + fenoxaprop-p-ethyl 1% MEC at 650, 825, 1000, and 1650 (only for phytotoxicity study) ml ha-1 as EPoE, pyrithiobac-sodium 10% EC at 750 ml ha-1 as EPoE, haloxyfop-R- methyl 10.5%w/w EC at 1250 ml ha-1 EPoE, fenoxaprop-p-ethyl 9.3% EC at 750 ml ha-1 EPoE,propaquizafop 10% EC at 625 ml ha-1 EPoE, hand weeding at 30 and 60 days after sowing (DAS), weed-free and control (water spray). The treatment involving pyrithiobac-sodium 7.5% + haloxyfop-R-methyl 13.5% + fenoxaprop-p-ethyl 1% MEC at 1000 ml ha-1 EPoE resulted in the lowest weed density and biomass, weed index, and higher weed control efficiency. The phytotoxicity effect was obtained in pyrithiobac-sodium 7.5% + haloxyfop-R-methyl 13.5% +fenoxaprop-p-ethyl 1% MEC at a higher dose of 1650 ml ha-1 , which was subsequently resolved. This treatment also showed a higher value of growth parameters and yield attributes,i.e., plant height, number of sympodial branches, green bolls, and picked bolls per plant, ultimately leading to a 60% increase in yield compared to the weedy control. A higher net return and B-C ratio were also obtained in this treatment.