The No. 103-1 hydrogeological borehole in Wangwa Coalmine happend a sand jamming accident in the drilling operation. In the process of dealing with the subsequent jamming accident， the casing milling barrel was also jammed in the borehole， and the casing milling barrel broke immediately after being pulled out. The fracture was not even and tilted to the edge， which formed a very complex accident in the borehole.First of all， there was too much sand in the mud. Second， the diameter of the surface casing was too small when the drill collar stuck， which made it difficult to deal with the accident.According to the characteristics of the accident in the hole， this paper introduces the treatment scheme of pulling out the surface casing first， replacing the large diameter surface casing， and then setting back the milling barrel and drill collar.In addition， the active drilling pipe， drill bit， extended casing milling barrel， and centralizing tool for casing milling accident were specially designed and processed， which could deal with the complicated stuck pipe accident successfully in time.This paper discusses in detail the processing process and measures of drilling accidents， summarizes the lessons and experience of the accident， which has a guiding and reference significance for dealing with similar stuck drilling accidents.