为揭示榧树属植物的遗传多样性水平和遗传结构状况，为种质资源评价、保护和利用提供理论依据，本试验以4个榧树属物种累计295个样本为研究对象，用筛选出的15对引物对所有样本进行SSR-PCR扩增，并将扩增产物进行毛细管电泳检测，探究其遗传多样性和遗传结构并进行聚类分析。结果表明：(1)以有效等位基因为标准，遗传多样性从高到低依次为巴山榧(多态位点百分率P=87.50%,期望杂合度H_e=0.396,Shannon’s信息指数I=0.740)、佛罗里达榧(P=86.67%,H_e=0.342,I=0.596)、四川榧(P=73.33%,H_e=0.285,I=0.480)、云南榧(P=57.57%,H_e=0.194,I=0.332)。(2)榧树属21个居群的居群内近交系数(F_is)平均值为0.174,居群间遗传系数(F_st)平均值为0.490,居群间基因流(N_m)为0.260,说明基因交流不频繁。榧树居群的居群总近交系数(F_it)值均大于F_is值，说明居群间的杂合水平要大于居群内。(3)分子方差分析结果表明，榧属植物的遗传变异主要来源于居群间，变异系数为58%。21个居群间的Nei’s标准遗传距离在0.018～2.453之间，平均值为0.609。总体而言遗传距离与地理距离呈正相关关系(r=0.759,P<0.05),而云南榧和巴山榧的遗传距离与地理距离之间没有显著的相关性。(4)21个居群的遗传相似系数在0.403～0.983之间。当相似系数为0.12时，可将4种榧树属物种21个居群分为2个大类，佛罗里达榧的1个居群为一大类，其余3个物种的20个居群为另一大类；当相似系数为0.58时，可将其分为4个大类。

To unveil the genetic diversity and structure of Torreya plants and lay a theoretical foundation for evaluating, protecting and utilizing germplasm resources, a total of 295 samples from 4 Torreya species were used as materials. After selection, 15 pairs of selected primers were employed for SSR-PCR amplification across all samples, and the amplification products were analyzed by capillary electrophores detection to explore their genetic diversity and structure, and cluster analysis was conducted. The results revealed the following insights:(1) Based on the effective allele, the genetic diversity from high to low was Torreya fargesii(P=87.50%, H_e=0.396, I=0.740), Torreya taxifolia(P=86.67%, H_e=0.342, I=0.596), Torreya parvifolia(P=73.33%, H_e=0.285, I=0.480), and Torreya yunnanensis(P=57.57%, H_e=0.194, I=0.332).(2) The average F_is value of 21 Torreya populations was 0.174, the average F_st value was 0.490, and the Nm was 0.260, indicating that gene exchange occurred infrequently. The F_it value of Torreya populations was greater than the Fis value, suggesting that the heterozygous level between populations was higher than that within populations.(3) The results of the analysis of molecular variance indicated that the genetic variation of Torreya plants mainly originated among populations with a variable coefficient of 58%. The Nei's standard genetic distance among 21 populations ranged from 0.018 to 2.453 with an average of 0.609. Overall, the genetic distance was positively correlated with the geographical distance(r=0.759, P<0.05), while there was no significant correlation between the genetic distance and geographical distance in T. yunnanensis and T. fargesii.(4) Genetic similarity coefficients among the 21 populations were ranged from 0.403 to 0.983. Using a threshold of 0.12, the populations were grouped into 2 major categories with T. taxifolia forming one category and the remaining 20 populations of the other three species another. At a threshold of 0.58, they could be divided into 4 major categories.