Abstract: Using the hybrids crossed by Pingyi Tiancha (Malus hupehensis (Pamp.) Rehd. var. pingyiensis Jiang) and Zha’ai Shandingzi (Malus baccata (L.) Borkh.), the control plants of the two parents and normal M. baccata as the experimental materials to observe the chromosome numbers and analysis the karyotype. The results of the ploidy determination indicated that the ploidy of these six leaf-wrinkled plants are all tetraploidy: 2n=4x=68, and one smooth-leaf plant is aneupoid: 2n=43. The karyotype formulas are 2n=4x=44m+24sm, 2n=4x=60m+8sm, 2n=4x=20m+48sm, 2n=4x=52m+16sm, 2n=4x=56m+12sm, 2n=4x=48m+20sm and 2n=22m+18sm+3st, respectively. The karyotype types are 1B, 2B, 2A, 2B, 1A, 1B and 2B, respectively. Which will enrich the utilization and breeding of apomictic rootstock resources in Malus.