Abstract: This article takes the north wing belt transportation main roadway of a mine as the engineeringbackground, and uses key stratum theory to analyze the reasonable height of the "Three Zones" of the overly-ing rock strata. It also employs FLAC3D numerical simulation software to investigate the movement law of o-verlying strata under the conditions of thick coal seams and high mining height. In view of the occurrence con-ditions and application purpose of the surrounding rock in the north wing belt transportation main roadway ofthe mine, the surrounding rock of this roadway is divided into two areas, and diferent support schemes are a-dopted-combined anchor-net-cable combined support and shed support. This research provides a reference forthe support of the roof roadway in upward mining of thick coal seamswith high mining height.

Key words: upward mining, key stratum, "Three Zones" height, surrounding rock control technology