Abstract: In order to decrease the loss of variant seedlings in tissue culture， the variant rate of sub cultured seedlings of ‘Hort 16A’ was dynamically monitored by AFLPs in the study. The AFLP analysis system was set up and optimized， and the genetic diversity of 75 samples of R7R11’s generations was studied too. The experiments showed that using 1 U restriction enzyme to digest 300 ng genomic DNA at 37 ℃ for 4 h in dual enzymes restriction could achieve the best effect. 1U T4 DNA ligase， 15 μL adpter and 2 μL ATP could get the best adpter ligation. The best dosage of preamplification primer was 08 μL （100 μmol·L-1） and that of the selective amplification of Taq polymerase was 025 （83 350 nkat·mL-1） μL. 8 pairs of primer whose number of amplified bands were the richest were selected. A total of 494 bands were amplified using these 8 pairs of primer， out of which 310 were polymorphic bands， and the polymorphic rate was 627%. The results showed that kiwis tissue subculture seedlings could maintain their genetic stability until the ninth generations. But from the tenth generation， the variant rate of sub cultured seedlings had an upward tendency.

Key words: kiwifruit（Actinidia chinenesis Planch）, AFLP analysis system, tissue culture variation , subculture seedling, dynamic monitoring