中文摘要：

动物线粒体DNA（mt DNA）具有在细胞中大量存在、缺少重组、多为母系遗传、缺少内含子以及进化速率高等特点,广泛应用于比较和进化基因组、种群遗传、物种鉴定和不同分类水平上的系统发生学研究。头足类作为软体动物门中的重要经济种类,其分类和系统进化研究历来是热点领域。本研究主要对头足类动物mt DNA组成与特点（包括基因组成、重排等）、常用mt DNA标记对其不同分类阶元的适用性以及线粒体基因片段和全基因组在头足类系统演化中的作用进行了阐述,并对其未来发展进行展望。

英文摘要：

Ow ing to lack of recombination,maternal inheritance,absence of introns and higher evolutionary rates,mitochondrial DNA（mt DNA） are extensively used for population genetics,species identification and phylogenetic relationships at various taxonomic levels.In recent studies,phylogenetic analysis based on mt DNA sequence data has been proved to enhance resolution and statistical confidence of inferred phylogenetic trees when compared with traditional taxonomic methods.Taxonomy and phylogeny of Cephalopoda,which is by far one the most important economic and diversity group of mollusks,have become the most intriguing field.Herein,we provided a brief introduction to the contents and the structures of mt DNA,and subsequently review ed the progress of mt DNA applied in cephalopod molecular systematics,especially the complete genome.Additionally,the research tendency of molecular systematics of cephalopods was discussed.