Abstract: The multi-stage fracturing horizontal well is one of the effective method to realize regional gas pre-drainage. Because the horizontal wells in the same mining area are put into production successively, the phenomenon of ' frac-hit ' that the new well fracturing affects the normal drainage of the old wells has appeared in the engineering application. Taking the horizontal well group in coal seam roof in Zhujidong Mine of Huainan Mining Area as the research object, the characteristics of frac-hit between new and legacy wells were analyzed, the types and inducing factors of frac-hit were discussed, and the rapid recovery method of old wells was proposed and applied. The results show that the bottom hole pressure (BHP) of the old well has different response characteristics when the fracturing treatment of the new well causes fracturing channeling to the old wells. According to the different connecting media between new and old wells, the types of inter-well frac-hit for horizontal wells in coal seam roof can be divided into three types, namely: stress shadow interference, indirect frac-hit and direct frac-hit. For the stress shadow interference type, the BHP response characteristics of the old well are slowly rising first, and decreasing rapidly after the fracturing treatment stops. For the direct frac-hit, the BHP of the old well increases sharply after the fracture communication between new and old wells. The main inducing factors of frac-hit for horizontal well group in Zhujidong Mine are small well spacing and faults / natural fractures in coal measure strata. According to the characteristics of horizontal well group, the rapid recovery measures of old well after frac-hit were put forward, that is, hydraulic sand washing of the frac-hit old well → rapid blowout and depressurization of new fracturing well → precise drainage and stepwise increasing gas production of the frac-hit old well. After the application of the re-production measures, the 3 frac-hit influenced wells re-produced quickly, and the gas production exceeded that before the frac-hit, and good results were achieved. The research results can provide reference for the prevention and control of frac-hit between new and old CBM extraction horizontal wells under similar conditions and the rapid re-production of frac-hit influenced wells.