Abstract: Predicting heterosis of two parents is the main reason for no breeding application of heterosis predicting methods. However, predicting heterosis between abortion line and cross combination is a practicable method and the method has been applied in developing rice restorer line of 3-line system. The cause of little achievement of the method was analyzed. The method could improve breeding efficiency significantly and was also called restorer line breeding method via F1 testcross and Fn testcross.