Twelve combinations (including the consrative group) of the sixth regional test of HeiLongJiang Province in 2003 were analysed by using the principle and mothed of grey comprehensive evalution and employed grey relativity analysis on several characters that affect the maize yield. The result shows the magnitude on effects of vary characters on the yield of immature maize in turn was leaf number, ear high, bald, ear length, kernel production ability, ear thickness, rows per ear, plant height, kernel per row, 100-grain weight.