Abstract: 【Objective】To research the correlation between ploidy levels and main characters in Phalaenopsis. 【Method】Ploidy levels of 85 Phalaenopsis accessions were identified by using squash method, and the length and density of stoma, the length, width and thickness of leaf, the diameter and the number of flowers were also measured. 【Result and conclusion】The results showed that in the 85 accessions there were three diploids (3.5%), nine triploids (10.6%) and 73 tetraploids (85.9%). Stomatal lengths and the length of tetraploid flower were obviously longer than those of diploid and triploid flower, while the density of stoma and the number of flowers were fewer than that of diploid and triploid(P<0.05). The differences of the stomatal cell length and diameter and the number of flower between diploid and triploid were not significant at 5% level, however, the stomatal density of triploid was less than that of diploid(P<0.05). The leaf length of tetraploid was significantly longer than that of diploid(P<0.05), while the difference of leaf length between diploid and triploid or between triploid and tetraploid was not significant(P>0.05). The difference of leaf width and thickness among diploid, triploid and teraploid were also not significant either(P>0.05).The ploidy levels were, to a large extant, positively associated to stomata length, leaf length and flower diameter, but negatively correlated with stomatal density and the number of flowers.