To examine the genetic origin of the domestic pig, the distribution of wild boar, and human-mediated translocation of the domestic pig, we collected 223 samples from domestic pigs and wild boars from eight Indonesian islands, sequenced the control region of mitochondrial DNA (mtDNA) from each sample, and compared these sequences with previously determined sequences from East and Southeast Asian domestic pigs and wild boars. Three Sus species (S. scrofa, S. verrucosus, and S. celebensis) were identified on the Indonesian islands. The mtDNA sequences of three Indonesian Sus species were diverse, and they clustered into three lineages with low bootstrap values (an S. scrofa group including East and Southeast Asian domestic pigs and wild boars, a group including indigenous S. scrofa together with S. verrucosus from Sumatra and Java Islands, and an S. celebensis group from Sulawesi Island). The mtDNA haplotypes of S. scrofa wild boars from three (Sumbawa, Flores and New Guinea) islands and domestic pigs from two (Lombok and Timor) islands east of the Wallace Line, and some S. scrofa wild boars from Sumatra and Java Islands were related to Vietnamese pig mtDNA sequences in the East and Southeast Asian domestic pig and wild boar clade, supporting that ancient immigrants likely introduced domestic pigs from the Asian continent to east Indonesian islands. The mtDNA haplotypes of S. celebensis were broadly divided into three groups, which were distributed in the north and southwest areas, central area and southeast area of Sulawesi Island.