Objective To study the genetic variation and inbreeding of Xishuangbanna miniature pig.Methods The polymorphism of 12 microsatellites loci in the Xishuangbanna miniature pig inbreed(XMI) was analysed. Results The dendrogram results based on genetic distance suggested no difference between XMI and their pedigree, and that rates of homologous genes in them were high. Conclusion XMI has many substrains with different characteristics and high inbreeding degree.