A field experiment was carried out for two consecutive years at the Research farm of Regional Agricultural Research Station, Nandyal during Kharif 2016-17 and 2017-18 with an objective to find out the effective and economic method of weed control in Bt cotton. Among different herbicide applications, pendimethalin 1.0 kg/ha as pre-emergence fb glyphosate 1.0 kg/ha as directed spray at 2-4 leaf stage weed + one hoeing at 50 DAS were significantly superior in reducing weed density and dry weight of weeds. The crop growth parameters (plant height, no of sympodia per plant), yield attributes (no. of bolls/m2 andboll weight) and seed cotton yield were recorded highest in weed free check (4.18 t/ha in 2016 and 3.23 t/ha in 2017) and was comparable with pendimethalin 1.0 kg/ha as pre-emergence fb glyphosate 1.0 kg/ha as directed spray at 2-4 leaf stage weed + one hoeing at 50 DAS. However, the lowest seed cotton yield was recorded under weedy check plot (1.62 t/ha in 2016 and 1.64 t/ha in 2017). Among weed control treatments, highest B:C ratio was recorded with application of pendimethalin 1.0 kg/ha as pre-emergence fb glyphosate 1.0 kg/ha as directed spray at 2-4 leaf stage weed+ one hoeing at 50 DAS closely fb weed free check.