泾原镇是唐廷于大历三年（768）在西北边疆设置的重镇。唐中后期，泾原因地处西塞之口和军事要道的战略位置，成为直接与异族对抗的前线阵地。在党项、吐蕃等异族不断寇扰和唐廷重构整个京西北边防的背景下，泾原镇逐渐建立。其军队主体为安史之乱后由安西、北庭分不同批次调出的精锐部队。建中四年（783）泾原军于长安发动“泾师之变”。通过分析事变前后唐廷和泾原在政策、举措等方面的不同，可以窥探唐廷与泾原关系的变化。泾师之变前，唐廷对泾原节度使的态度经历了从代宗赏赐优待到德宗强硬打压的转变；泾原军因两次被要求移镇而爆发了王童之之乱和刘文喜之乱，对唐廷的怨恨情绪和骄悍性格逐渐养成，这些成为促成泾师之变的重要原因。泾师之变后，唐廷调整了对泾原的政策。经济上，在中央财政拮据的情况下，令泾原通过军事屯田自筹军资，改善内地赡军和仰给度支的经济状况；政治军事上，通过设置神策军镇和选派禁军将领出镇泾原等方式，重新确立对泾原的统御和控制。

In this paper, a thorough study was conducted on Jingyuan province in the middle and late Tang dynasty. Established in 768, Jingyuan province was a key province in the northwest borderland. Located in the northwest gateway and being the main military channel, Jingyuan was the frontier of the resistance to non-Han people. Facing the frequent invasion of northwest ethnic such as Tangut and Tibet, the Tang dynasty reconstructed the whole northwest borderland. Jingyuan province was established gradually in this background. The majority of its military forces are different batches of elite troops transferred from Anxi and Beiting Protectorate after the rebellion of An Lushan. The relationship between Tang court and Jingyuan province before and after the rebellion of Jingyuan is discussed through the comparison of the policies, measures and other aspects. Before the rebellion, the Tang dynasty’s attitude towards Jingyuan governors changed from the preferential treatment of Daizong to the strong repression of Dezong. Led by Wang Tongzhi and Liu wenxi, Jingyuan’s army broke up with rebellion when they were forced to change the garrison twice. It’s resentment and aggressive character toward the Tang government gradually formed. These contributed to the outbreak of the rebellion of Jingyuan. After the rebellion, the Tang dynasty adjusted its policy. On the economic aspect, due to the financial constraints on the central level, Jingyuan province raised military funds through military farming, which reduced its economic dependence on inland and central government. On the political and military aspect, by setting up military town belonging to the Army of Inspired Strategy and selecting generals from the Imperial Army to govern Jingyuan，the Tang government reestablished the unity and control of Jingyuan province.