In this study, we have determined the complete nucleotide sequence of the mitochondrial genome of Octopus dollfusi (Robson, 1932) collected from the coast of Guangdong Province, China, and analyzed the phylogenetic relationship with other cephalopod species. The results show that the mitochondrial genome of O. dollfusi composed of 15843 nucleotide pairs and encodes 13 proteins, 2 ribosomal RNAs (rRNAs), 22 transfer RNAs (tRNAs) and a major long noncoding region (LNCR) of the mitochondrion’s own protein synthesizing system. Seven of thirteen proteins, eight tRNAs are encoded by the plus strand, while the other proteins and tRNAs, as well as two rRNAs are encoded by the minus strand. Two (ND4 and ND4L) of the 13 protein coding genes of O. dollfusi began with the unorthodox translation initiation codon ATA and all others use the standard ATG. Ten protein-coding genes use TAA as the termination codon and the rest share the termination codon TAG. There are five cases where tRNA genes appear to overlap. The LNCR of O. dollfusi was 926 nucleotides and no repeated sequences were found in this LNCR. Phylogenetic analysis of 24 cephalopoda species based on the complete mitochondrial genome showed that the O. dollfusi is most closely related to Amphioctopus aegina. These results seems to support the recent notion that O. dollfusi should be considered as synonym of Amphioctopus aegina. More morphologic and molecular evidences should be involved to resolve the taxonomic status of O. dollfusi in future’s studies.