清朝在东北的封禁政策在不同时期有不同的内容。清廷主动确立封禁东北政策。但在内忧外患的背景下,被动地调整封禁政策。期间经历了封禁——弛禁——解禁的演变过程。在此演变下,东北边防受其影响,经历了漫长而曲折的发展历程。 The Qing banning policy in the northeast has different contents in different periods. Qing court took the initiative to establish a ban on northeast policy. However, in the context of internal and external disasters, the ban policy is passively adjusted. During the embargo - to relax - lift the evolution of the ban. Under this evolution, the northeast frontier defense has experienced its long and tortuous course of development.