Abstract: Effects of enhanced UV-B radiation on the phenology of wheat and maize were investigated. Results show that at the grown stage, the phenology of wheat and maize were postponed significantly by enhanced UV-B radiation. The experiment also shows that the germination of wheat and maize were also postponed significantly by enhanced UV-B radiation, which indicated that the effect of enhanced UV-B radiation to the phenology of wheat and maize were not attributed to the nutrition available. The microclimate of crop was also influenced by enhanced UV-B radiation, showing that the temperature of canopy and soil raised significantly. Indicated that the effect of enhanced UV-B radiation to the phenology of wheat and maize were not attributed to the change of microclimate in response to enhanced UV-B radiation. The possible mechanism of the change of crop phenology in response to enhanced UV-B is discussed, and the problem be supposed to be investigated further is also put forwarded in the paper.