Induced mutagenesis creates new allelic combination of genes without disturbing the basic genomic structure of the plant. Effectiveness relates mutagen dose to mutational events, while mutagenic efficiency shows the proportion of mutations in relation to biological damage in M1 generation. Present investigation was undertaken to assess the effectiveness and efficiency of different individual and combination treatments of gamma rays and EMS in M2 generation of black gram. Mutagenic effectiveness and efficiency were calculated in relation to biological damage in M1 and chlorophyll mutations in M2 generation. The order of mutagenic effectiveness based upon the percent of mutated plant progenies was EMS > gamma rays+EMS > gamma rays. Combination treatments of gamma rays+EMS were found to be the most efficient followed by the individual treatments of EMS and gamma rays in both the varieties. Moderate doses of gamma rays and EMS alone as well as in combination proved more effective and efficient in inducing mutations. Among the varieties, variety Pant U-30 proved more responsive towards mutagenic treatments than the variety T-9. These results not only provide valuable information about mutagenic treatments and germplasm resources of black gram, but also provide guidance for generating black gram mutants through mutation breeding.