Variation in genetic constituent leads to increasing phenotypic expression of the quantitative characters of individuals. This variation is induced by mutation and the variability was evaluated on the quantitative traits such as, days to germination, percent germination, root length, brix percent and yield of sugarbeet mutant at M1 generation by the effect of radiation. The results were showed higher genetic variability, heritability, genetic advance with significant uplift in yield and the related ones. Hence selection is effective considering these traits from a gamma ray irradiated population. The gamma rays irradiation induced addition-deletion in DNA pairs and also reshuffle chromosomal component. The results were showed significant enhancement in yield and related traits. It indicates that improvement in quantitative traits would be possible through gamma rays irradiation.