Three chestnut species, Castanea mollissima, C. seguinii, and C. henryi, are endemic in China. These chestnuts have traditionally been divided into 5 cultivar groups, those from the Yangtze River Valley, and from Northern, Southeastern, Southwestern, and Northwestern China. The Chinese chestnut, Castanea mollissima from Hebei Province belongs to the Northern China group. These chestnuts are cultivated in two climatic regions, the Yanshan and Taihangshan Mountains. The objective of this paper was to determine the genetic diversity of Castanea mollissima from Hebei and Shan Dong Provinces using inter-simple sequence repeat (ISSR) markers. Using 19 primers, 93 bands were produced in 15 cultivars. Thirteen of these cultivars were from Hebei, and two were from Shandong. Of the 93 bands obtained, 31 (33.3%) were polymorphic. Phylogenetic analysis using Unweighted Pair Group Method with Arithmetic Mean (UPGMA) in PHYLIP Package3.6 separated the tested cultivars into 3 groups. One is composed of cultivars from Yanshan Mountains. Another is composed cultivars from Yanshan Mountains and from Shan Dong. The rest of the cultivars are from Thihangshan Mountains. The result showed that an original chestnut from Hebei may have diverged by geographic separation to produce different genotypes now growing in the Yanshan and Taihangshan Mountains.
