A field experiment was conducted during rainy seasons of 2014 and 2015 at College of Agriculture, Gwalior (M.P.) to study the effect of herbicides in blackgram. The experiment was laid out with 12 treatments, viz. imazethapyr with four application rates 70 and 80 g/ha as pre-emergence (PE) and 70 and 80 g/ha as post-emergence (PoE); imazethapyr + imazamox (RM) 70 and 80 g/ha as PE, and 70 and 80 g/ha as PoE, pendimethalin 1000 g/ha as PE, pendimethalin + imazethapyr (RM) 1000 g/ha PE, two hand weedings at 20 and 40 DAS (weed free) and weedy check in a randomized block design. Two hand weeding at 20 and 40 DAS were found to be very efficient in controlling the dominant grassy weeds and gave maximum seed yield (924 kg/ha) fb ready mix herbicides i.e. imazethapyr + imazamox 80 g/ha as PoE (905 kg/ha) and pendimethalin + imazethapyr 1000 g/ha as PE (879 kg/ha). Net returns and B:C ratio were the highest for the application of pendimethalin + imazethapyr (1000 g/ha PE) (3.32) fb application of imazethapyr + imazamox (80 g/ha PoE) (3.11).