1934年,刘长胜接受共产国际的一项重要任务,把密电码带回中国直接交给中共中央,以恢复中断多年的电讯联系。他打扮成北方商人,历经千难万险,千方百计打听党中央所在地,历时一年余,终于到达瓦窑堡,把密电码交给党中央。毛泽东表扬他为党立了一功。他在延安任中华全国总工会西北 In 1934, Liu Changsheng accepted an important task of the Comintern to bring the secret code back to China directly to the Central Committee of the Chinese Communist Party to resume the interruption of the telecommunications connection for many years. He dressed as a northern businessman, after numerous troubles and dangers, do everything possible to inquire about the location of the party Central Committee, which lasted more than a year, finally arrived Wayaobao, the secret code to the Central Party. Mao Zedong praised him for having made a victory for the party. He was appointed as the All-China Federation of Trade Unions in Yanan Northwest