Abstract: CO₂ fracturing technology is a kind of new physical blasting technology, and the blasting process is without flames leakage, and it can effectively be used in coal and gas outburst mines. In this article, through the analysis of fracturing mechanism of carbon dioxide, we confirm that single-hole blasting crack length is 0.5 m, and the crack number is 3.5. According to theoretical anlysis, we arranged hole in Chengzhuang Mine to control floor heave, it has obtained the good effect; the measured crack length and numbers are in accordance with the theoretical calculation values.