Correlation and regression of flag leaf traits and yield traits were studied using 14 varieties of spring wheat.The experimental results showed that the flag leaf length,flag leaf width,flag leaf area and chlorophyll content of flag leaf were positively related to grain number per spike,1000-grain weight,grain weight per spike and grain yield.The angle between flag leaf and stem were related negatively with grain yield.The multiple regression equations between flag leaf traits and yield characters were founded.