Gamma radiation can be utilized as a mutagenic agent for inducing genetic variability in plant species. The present study was carried out to increase genetic variability and evaluate the effectiveness of different gamma rays doses (0, 10, 20, 30, and 40 Gy) on germination & survival percentage, plant height, number of branches/plant, tuber weight, total yield/plant, inulin, and dry matter percentage of two Jerusalem artichoke (Helianthus tuberosus L.) genotypes (Balady and Fuseau) during 2019 and 2020 seasons at the Experimental Farm of Kaha Research Farm, Kaluobia Governorate, Egypt. Results showed that a 10 Gy dose of gamma irradiation significantly increased plant height, tuber weight, yield per plant, dry matter, and inulin concentration. Increasing gamma-ray doses significantly reduced values for all of the studied traits, but the number of branches/plant increased with increased gamma-ray doses. According to the results of this study, gamma rays may cause mutations in Jerusalem artichoke through their three mutagenic treatments, and they can also improve several quantitative features. The high heritability and genetic advanced values suggest that future generations may see additional advancements.