【研究目的】明确中国兰花品种间在DNA水平上的遗传多样性和亲缘关系。【方法】应用ERAPD（延长随机引物扩增）、叶绿体和线粒体基因组PCR-RFLP对21个中国兰花品种进行分子鉴定。【结果】RAPD分析中共有8个(10%)引物和88条(83.81%)多态性带纹；ERAPD分析中能获得一条2.5KbRAPD特异性片段；叶绿体基因组（cpDNA）的PCR-RFLP分析中有4个（66.67%）引物和12个(25%)引物-酶组合；线粒体基因组中（mtDNA）的PCR-RFLP分析中有2个（33.33%）引物和1个（4%）引物-酶组合能揭示材料间遗传差异。【结论】3种分子标记均能揭示品种间在DNA水平上存在遗传差异，而且遗传学分类与形态学分类基本吻合。

【objective】In order to reveal the genetic variations and relationship of 21 Chinese cymbidium cultivars.【Method】21 cultivars from 7 cymbidium species were analyzed by ERAPD, cpDNA and mtDNA PCR-RFLP markers.【Result】Eighty-eight polymorphic bands are observed in 8 out of 80 random primers (10%) in RAPD analyses, the 2.5-kb RAPD fragment are obtained in ERAPD analysis, Genetic difference are revealed in 4 primers （66.67%）and 12 primer-enzyme combinations(25%) by cpDNA PCR-RFLP analysis, 2 primers （33.33%）and 1 primer-enzyme combinations(4%) by mtDNA PCR-RFLP analysis.【conclusion】The results indicate that these molecular markers can detect the genetic difference in 21 Chinese cymbidium cultivars.