本文通过统计分析和数据处理测定了25个玉米自交系间遗传距离,并聚成7类。通过遗传距离的测定和分析现有推广的杂交种亲本之间的遗传距离都大于类内平均距离,因此,类群间差异较大遗传距离较大的自交系做为杂交组合的亲本为好。以自交系间表现型和地理起源的差异不能代替遗传距离上的差异。遗传距离的分析,对自交系的选育、改良群体、选配杂交组合可提供科学依据,所以遗传距离是重要的遗传参数。 In this paper, the genetic distance of 25 maize inbred lines was determined by statistical analysis and data processing, and clustered into 7 categories. Therefore, it is better that the inbreds with larger genetic distance among the groups are the parents of the crosses, as measured and analyzed by the genetic distance. Differences in phenotypic and geographical origin of inbred lines can not replace differences in genetic distance. Genetic distance analysis, selection of inbred lines, improved populations, optional hybrid combinations provide a scientific basis, genetic distance is an important genetic parameter.