The invention relates to a middle-deep hole blasting intra-hole cushion layer supporting device. The supporting device comprises a cylindrical part with circular holes in the middle area and disc-shaped parts which are arranged at the upper end and the lower end of the cylindrical part correspondingly, and a circular hole is also formed in the middle area of each disc-shaped part. According to thesupporting device, the structure is simple, the operation is convenient, not only the use rate of explosive energy can be improved, but also the boulder yield is reduced, the explosion quality is improved, and the device has a very ideal technical effect.