After the movement of “March13th” anti-Japanese demonstration, the Korean anti-Japanese communities which were active around Yanbian in China set up to build up anti-Japanese arms respectively and embarked on the path of resisting Japanese imperialism with their own arm force. This was regarded as a severe problem by the Japanese Imperial who tried to use Yanbian as a stronghold to take control of the whole Northeast China and then carry out its “invading policy of the mainland China”. After the trick of using the Chinese army in Northeast to control Korean people failed, Japan sent more the 20thousand regular forces to attack Yanbian on the excuse of “Hunchun Event”, making the “Gengshen tragedy” which astonished people from home and abroad. The cruel invasion of Japanese Army did not defeat the anti-Japanese forces. Quite on the contrary, it greatly strengthened their resolution to fight back. Anti-Japanese army organized “Counterattack War of the Gengsheng year” actively, gravely smarting the Japanese army in both the eastern and western fronts.