A multistage dissociation-machine-column joint re-separation process for an intermediate coal coproduct of a coking fat coal, related to coal separation methods. An intermediate coal of the coking fat coal is fed into a quick coarse grinding apparatus; a product produced from coarse grinding is fed into a screening apparatus; the product on a primary screen is returned and fed into the quick coarse grinding apparatus, the product under the primary screen is feed into a separating apparatus, and a primary separated cleaned coal is fed into a fine grinding apparatus; a product produced from find grinding is fed into a screening apparatus for secondary screening, the product on a secondary screen is returned and fed into the fine grinding apparatus, the product under the secondary screen is fed into a screening apparatus for tertiary screening; the product on a screen is fed into a secondary separating apparatus to complete separation, and the product under the screen is fed into a serial-connected separating apparatus to complete separation. Implemented is the dissociation of the intermediate coal coproduct of fine embedded granularity, the employment graded flotation effectively increases the recovery rate of coarse particles and the selectivity of fine particles, ensured are clean coal recovery rate and clean coal ash content, the process is simple and reliable, and clean coal in the intermediate coal of the coking fat coal is recovered to the greatest extent.