In view of the problems of broken peripheral rock of the roadway under the top coal damage area, which leads to difficulties in expanding the gangs, Hanzui Coal Industry took the 32101 working face cutting eye as the research object, analysed the destabilisation mechanism of the roadway expanding the gangs in the top coal damage area; and put forward the control technology of the peripheral rock of the top plate pre-grouting, which is based on the formation of the slurry stopping curtain, and then constructed a regenerated top plate by grouting. Through numerical simulation to verify the reinforcement effect, the results show that the plastic zone range of the roadway is significantly reduced after grouting; the field application results show that: after adopting the roof pre-grouting reinforcement measures, the maximum amount of the top and bottom plates of the peripheral rock of the cutting eye of the working face of 32101 was 160 mm, and the maximum amount of the two gangs was 129 mm, which is a good effect of the reinforcement of the peripheral rock.