Abstract: The reasonable aspect ratio is one of the key factor to ensure roadway stability. In order to obtain the deformation characteristics of surrounding rock influenced by the reasonable aspect ratio of large section roadway, the article analyzed the deformation characteristics of roadway under different widths and heights by using numerical simulation. It has been shown that the reasonable aspect ratio of roadway is about 1. The displacement of surrounding rock gradually increases with the increase of width and height of roadway, there is a reasonable aspect ratio, the displacement significantly increases after more than the reasonable aspect ratio, the surrounding rock shows overall mobile trend and produce separation, and finally the roadway is damaged by the style of slip instability. The roadway is supported by the technology of high pre-stressed bolt and anchor according to the specific geological condition and the deformation characteristics of large section roadway. Engineering applications show that the deformation of surrounding rock has been effectively controlled.