Abstract:There are many kinds of torpedo defense equipment in the world, and new equipment emerge in endlessly. Thispaper analyzes defects of soft killing and hard killing means of present torpedoes, and focuses on the limitation of anti-torpedo torpe-do ( ATT). Comparing with the aerial anti-missile system, this paper points out the present technical misunderstanding of ATT. Fi-nally, a torpedo close-in defense method is given: a moving depth charge array is formed by several depth charges, and the coopera-tive operation of depth charges is adopted for torpedo defense.