中文摘要：

19世纪后期新疆屯垦事业弛废，由此出现了新的边疆危局，主要表现在新疆内部连续发生动乱，而外部又面临着俄、英等帝国主义的入侵。如何应对西北边疆危局，成为清政府面对的重要课题。左宗棠果断进兵新疆、平定危机，成为清代后期成功处理边疆问题的范例。这其中既与国家决策果断、用兵及时有关，也与此前新疆屯垦发展和此后新疆屯垦逐渐完备有关。该文通过对边疆危局的原因、过程和影响进行梳理，分析出新疆屯垦事业与西北安防的内在机理。

英文摘要：

In the late nineteenth century, stationing and land reclamation in Xinjiang which was neglected by the Qing government led to a new frontier on the verge, mainly in the internal unrest and foreign invaders, so the Qing government in dealing with the north west frontier into a critical situation fell into a difficult strategic choice. Zuo Zongtang decisively launched a war with hostile forces in Xinjiang and won the war because it was not only a decisive decision and direct military operation in a time, but also followed with the stationing and land reclamation development in Xinjiang, so Xinjiang had achieved social stability. This behavior also became a successful example of dealing with border issues in the late Qing Dynasty. This article researched the reasons of the event, the process of the event, the impact of the event, and analyzed the internal security mechanism between the stationing and land reclamation of Xinjiang and social security in the northwest.