The aim of this study was to evaluate the appropriate concentrations of plant hormones from (10-5) to (10-7 M) concentrations over UV-B damage on Brassica campestris and Brassica juncea in case of protease and peroxidase enzyme extraction. Seeds of both varieties were grown in the laboratory for the seed germination & seedling growth with appropriate concentrations of plant hormones for the isolation of enzyme protease and peroxidase. The protease activity was also enhanced in the germinating seeds of both varieties of mustard crops due to the UV-B exposure as compared to the control. When the seeds were supplied with plant hormones viz. IAA, Kn & GA3 along with UV-B treatment, which changed significantly & decreased in Brassica compestris & Brassica juncea respectively as compared to UV-B exposure alone. A marked increase in peroxidase was noted in inhibited seeds of both the crops due to UV-B radiation recorded in Brassica compestris & Brassica juncea respectively due to UV-B radiation as compared to control. When the seeds were supplied with plant growth hormones along with UV-B radiation, this effect was altered significantly and a decrease was reported in Brassica compestris & Brassica juncea as compared to the UV-B exposure only.