The invention belongs to the technical field of bottom tilling machines, and particularly relates to a transmission chain scarification type double-shaft smashed tilling and bottom tilling machine. The machine comprises a rack, a traction suspension device and a transmission device, wherein the transmission device comprises a steering gear and a rotary main shaft which is in transmission connection with the steering gear; soil cutting knife discs are symmetrically fixed on the rack; the soil cutting knife discs are in transmission connection with the rotary main shaft, and semi-closed scarification transmission chains are arranged behind the soil cutting knife discs at the two sides; the semi-closed soil scarification chains are symmetrically fixed to the rack and are in transmission connection with the rotary main shaft, scarification blades are uniformly fixed to the surfaces of the semi-closed scarification transmission chains, and a cutter shaft is fixed between the semi-closed scarification transmission chains at the two sides; the cutter shaft is in transmission connection with the semi-closed scarification transmission chains through chain wheels, and a plurality of bottom tilling cutters are uniformly arrayed on the cutter shaft. The transmission chain scarification type double-shaft smashed tilling and bottom tilling machine can achieve bottom tilling, is beneficial tocrop root growth, can prevent the water loss, increases the crop yield, and increases the income of farmers.