In order to study the coal mining technology under industry square, this paper, based on the “Three Unders” mining in Wumuchong Coal Mine and combined with the actual on-site situation, proposes three different mining methods, i.e. mining method reaming coal pillars under important buildings (scheme 1), mining method reaming coal pillars under important buildings and controlling deformation level and repairing after mining under common buildings (scheme 2), and mining method reaming a little coal pillars under important buildings and backfill mining under common buildings (scheme 3). By analyzing the surface deformation caused by caving method, strips mining method and backfill mining, this paper predicts the surface deformation and the influence on buildings produced by three different mining schemes. After analyzing the above three schemes from the perspectives of technology and economy, this paper considers that scheme 3 has a very slight effect on surface buildings, recycles more coal resource and yields good economic benefits, which is applicable to coal mining under industry square.