The advantage of the school is a popular issue that has not fallen for thousands of years. The advantage of the school can create a high-quality learning environment and teaching quality to ensure that students can obtain a channel of competitiveness. In this study, we adopted the Delphi technique and invited 100 primary school principals to conduct a three-round survey and review. Based on the literature of factors related to school advantages, the aim on a principal questionnaire with 99 items. The survey of domestic primary school principals was conducted, and 149 valid samples were obtained. According to the exploratory factor analysis (EFA) method, 25 repeated analysis progresses were examed on the results of the principal questionnaire. Eventually, the construction of the school's advantage evaluation index, that is, the 9 items of the reciprocity of teaching quality and the 8 items of the stability of long-term development, provide accurate, convenient and feasible reference strategies for shaping the school's advantages.