The invention relates to a soft coal step-by-step zooming hydraulic fracturing anatonosis device and method, relating to the field of coal mine gas extraction. A hydraulic fracturing anatonosis deviceincludes a hole sealing device and a hydraulic fracturing device. The method contains the following steps: S1, classifying coal strength from the near to the distant according to field coal-rock massactual measurement regional tectonic distribution, coal mass joints and pore and fracture development situations, determining coal bed joints and pore and fracture development situations as well as coal strength, and forming gas extraction fracturing drill holes; S2, efficiently sealing the gas extraction fracturing drill holes by adopting a hole sealing device; and S3, carrying out step-by-stepzooming hydraulic fracturing on the gas extraction fracturing drill holes by adopting the hydraulic fracturing device. According to the device and the method which are provided by the invention, fractures in coal-rock masses can be extended to the utmost extent when being sufficiently developed, strong support is provided by follow-up efficient gas extraction, and a technical guarantee is providedfor precise gas extraction of a working surface and safe production.