Ultraviolet radiation suppressed growth, elevated the content of ABA, and enhanced the evolution of ethylene in the mutants of Arabidopsis thaliana(L.) Heynh. As the radiation dosage rose, all the characteristics increased. Among the three lines studied (Enkheime, E 6 glabra, and vc"er"gl"an"), the plants of the latter were the most resistant to UV radiation. They were also notable for a higher level of ABA both before and after radiation treatment and greater evolution of ethylene after the exposure to radiation. The study of vc, er, gl, and anpoint mutants showed that the ermutant was the most resistant and the glmutant was the most sensitive. The results obtained suggest that the resistance of the vc"er"gl"anline primarily depending on ermutation was related to high levels of ethylene evolution and ABA under UV-B stress.