Abstract: This study used the main cultivated variety of Lycium barbarum ‘Ningqi No.1’ in Ningxia as the reference to compare the mitochondrial genome（mtDNA） of similarities and differences in structural composition and genetic relationship with that of other six Solanaceae plants reported in present, including Capsicum annuum, Solanum melongena, S. tuberosum, S. lycopersicum, Hyoscyamus niger and Nicotiana tabacum. The aspects of gene composition, intron distribution, homologous collinearity, conserved gene cluster, repeat sequence and phylogenetic evolution were compared. The results showed that the size of mtDNA among different species of Solanaceae plants varied greatly, ranged from 413 881 bp（Lycium barbarum） to 688 698 bp（Solanum tuberosum）, the number of genes was between 61 and 71, the protein-coding genes contained in Lycium barbarum and Capsicum annuum showed single copy, while other Solanaceae plants showed different degrees of multiple copies. Lycium barbarum shared more conserved gene clusters with Solanum melongena（16）, S. tuberosum（16） and Hyoscyamus niger（15）. In the analysis of mtDNA repeat sequences, Lycium barbarum had similar number of repeat sequences with Capsicum annuum. However, the number of simple sequence repeat and dispersed sequence repeat with length ＞ 1 000 bp in Lycium barbarum were the least in the Solanaceae plants compared. Phylogenetic analysis showed that Lycium barbarum had the closest genetic relationship with Hyoscyamus niger, and the furthest genetic relationship with Nicotiana tabacum. These results will provide a reference for further revealing the structural changes and functional studies of the mitochondrial genome during the Solanaceae plants evolution.