Abstract: Aiming at the harm of pulverized coal production in horizontal wells in broken soft and low permeability coal seams, A new concept of hydraulic jet perforation and fracturing is proposed，It can realize permeability enhancement and pulverized coal control,the specific processes include hydraulic jet perforation, high-pressure jet, annulus fracturing and hydraulic jet perforation cleaning.Through the comparison of cost and process, drag tubing hydraulic sand blasting perforation fracturing is selected, and the process and key tools are optimized. First, optimize the integrated cemented carbide conical convergent nozzle to prevent reverse erosion damage, which can achieve a jet pressure of 16.5-25.8MPa when the displacement is 2.0-2.5m3/min. Secondly, optimize the ejector body, which can effectively shoot through the casing and cement plug, and shoot into the rock to a certain depth. The supporting integrated string successfully completed the construction of 8-stage fracturing and 8-stage supplementary perforation of coalbed methane U-shaped horizontal well. The perforation time of each section is more than 15min, and fully displace the backflow pulverized coal, after three years of operation, the gas production still reaches more than 3500m3/d, it shows that the optimized process has achieved the transformation effect of broken soft and low permeability coal seams. Compared with coiled tubing staged fracturing technology,The single-stage fracturing operation cost through hydraulic jet fracturing by dragging tubing has been reduced by 28.5%.