Genetic stability of 24 sweetpotato germplasms maintained in vitro more than 5 years in the National Sweetpotato in vitro Genebank in Xuzhou, was analyzed using Simple Sequence Repeat (SSR) molecular markers. 20 pairs SSR primers were used. The results showed that all sweetpotato germplasms stored in vitro had the same amplified products as the controls preserved in field nursery, indicating that the two different methods have the same effect on preserving sweetpotato germplasm stability. Meanwhile, we analyzed the genetic diversity of 24 sweetpotato germplasms. The dendrogram generated by UPMGA showed the genetic relationship among 24 accessions. The genetic similarity among 24 accessions varied from 0.57 to 0.93. The numbers of total bands and polymorphic bands generated by the 20 primer combinations were 30 and 21 respectively. The 24 accessions were divided into 3 groups by cluster analysis. These results may provide a theoretical basis for sweetpotato germplasms maintained in vitro and the breeding of sweetpotato.