Abstract: To estimate the effects of enhanced ultraviolet radiation-B on upgrowth of maize and design answerer plans，the article studied influence of enhanced ultraviolet radiation-B on maize in middle-high elevation and arid regions. Used lift lamp of UV-B，we observed plant height、leaf area、green leaf number and yield structure of maize at different UV-B exposure dose in field condition. Field trail indicated that enhanced UV-B reduced plant height of wheat、leaf area、green leaf number and yield of maize in middle-high elevation and arid regions . The reasons that single leaf area lessen are both leaf length and leaf width decreased. Because yield structure become bad ，yield of maize reduce. More UV-B radiation, lower yield of maize.