Peanut is an important oil crop. However, food safety and industrial development of peanuts were limited by aflatoxin contamination. Breeding and applying resistant varieties have been effective approaches for aflatoxin control. However, progress in the identification of resistant germplasm resources and resistance breeding programs was hampered by complex, costly and unreasonable methods of A. flavus infection resistance in peanut seeds. In this study, the classification of peanut seeds after infected by A. flavus in the evaluation method was optimized and adjusted based on previous methods.The previous score for A. flavus infectione to peanuts seeds with 4 levels (referred to as "4-level score") was improved to 9 levels (referred to as "9-level score"). The results from evaluating peanut seeds infection with A. flavus using the 9-level score showed that it could better distinguish the difference inthe A. flavus infectionresistance among peanut varieties compared to the 4-level score. Furthermore, the results of comparing 9-level score and 4-level score were used in screening the A. flavus infection in a hybrid progeny population showed, the 9-level score was more efficient in identifying resistant materials and detected more QTLs in genetic linkage analysis. These results indicate that the 9-level score is an effective and stable index for A. flavus resistance peanut evaluation.