Abstract: Objectives To analyze the MSTN gene of Tibet mini-pigs，WU Zhi-shan mini-pigs，Bama mini-pigs and Guizhou mini-pigs.Methods Taking 42 Tibet mini-pigs，17 Wu Zhi-shan mini-pigs，7 Bama mini-pigs and 22 Guizhou mini-pigs as samples，PCR-RFLP polymorphism analysis on the controllable region of the MSTN gene 5’of pigs were carried out.42 Tibet mini-pigs were used to analyze the relation between the RFLP polymorphism of MSTN gene and some breeding characters（weight at birth（WB）and weaning weight（WW））.Results（l）There is significant difference in genetype frequencies and allele frequencies between different stocks of pigs（P=0.000）.Tibet mini-pigs have three MSTN genetypes TT（9.52%）、AA（61.90%）、TA（28.57%）、and the frequencies of alleles T and A is 23.81%and 76.19%respectively；Wu Zhi-shan mini-pigs have two genetypes TT（82.35%）、AA（17.65%）、and the frequencies of alleles T and A is 82.35%and 17.65%respectively；Guizhou minipigs have two genetypes TT（81.82%）、TA（1 8.18%）、and the frequencies of alleles T and A is 90.91%and 9.09%respectively；Bama mini-pigs have two genetypes TT（71.43%）、TA（28.57%）、and the frequencies of alleles T and A is 85.71%and 14.29%respectively.（2）The difference of WB（P=0.761）and WW（P