Dry and healthy seeds of two lentil cultivars, LH90-54 (macrosperma) and LH89-48 (microsperma) were treated with three doses of ethyl methane sulphonate (0.1, 0.2 and 0.4 %). In both the cultivars, all the M, plants with sufficient seed from each treatment and control were taken to raise independent M2 plant progenies. Wider range of means in both positive and negative directions along with overall positive shift in mean for all the polygenic traits, except pod-initiation height and 100-seed weight, were observed in different treatments in M2 generation. In both the cultivars, medium dose induced highest amount of variation. The estimates of variance, GCV and PCV for different polygenic traits increased significantly over control values in all the treatments of both the cultivars. Higher estimates of heritability and genetic advance in M2 population indicated tremendous scope for the improvement of seed yield and its component traits through selection in the mutagenized material.