Abstract: According to the deformation,failure and complicated migration law of the overburden strata above the fully-mechanized caving mining face ,which is affecte d to the stbility of the powered supports. Using the engineering practice of No. 1123 working face,the site-measurement,theoretic analysis and similar simulation experime nt are applied to study the main factors of inclined,mining height and working resistance of support which are effect the stability of powered supports.The results showed th at the influence degree of each factor to the powered supports stability was inclined,mining height and working resistance of support in sequence.The loading features of th e powered supports showed that powered support loading along the inclined direction of middle coal mining face and middle upper coal mining face is big,the powered sup port loading change was big in the top coal mining face. The displacement features of the powered supports showed that the shield support along mining face has tendency trend and middle region tendency trend was more outstanding than others,the shield supports along the middle upper were effected by baseplate change which lead to the shield supports base had the tendency trend along the mining face.In addition,the paper put forward the powered supports instability measures.