In the present study, pure line seeds of mungbean (Vigna radiata L. Wilczek) were treated with four doses (0.2%, 0.4%, 0.6% and 0.8% as w/v) of ethyl methane sulphonate (EMS) to analyse the genetic variability and heritability for some prime agro-metrical traits in second mutant (M2) generation. The analysis of variance revealed highly significant differences among the studied characters. The phenotypic coefficient of variation (PCV) was higher than its genotypic counterpart (GCV) for all the studied traits. The highest GCV (0.537) for number of seeds per pods and highest PCV (0.635) for plant height were recorded in 0.4% EMS treatment. The lowest GCV (0.179) and PCV (0.214) were recorded in the control set for number of pods per plant. The highest broad sense heritability estimate (92.33%) was recorded on 0.4% EMS for plant height. The expected genetic advance was high (42.39%) in 0.4% dose for days to flowering. The lowest heritability (38.43) and genetic advance (5.37) were noticed in control for the total seed yield per plant. EMS at 0.4% and 0.6% concentration gave the maximum values of all the genetic parameters. The increased genetic variability in treated population for these traits has a high scope for selection and can be exploited for the further improvement of mungbean.