The invention belongs to the technical field of bottom-tillage machines and particularly relates to a double-shaft powder-tillage bottom-tillage machine. The machine comprises a stander, a traction suspension device and a transmission device, wherein the transmission device comprises a steering device and a rotating main shaft in transmission connection with the steering device, ditching discs aresymmetrically arranged on the stander, a plurality of ditching blades are annularly arrayed on the ditching discs and are in transmission connection with the rotating main shaft, and transmission boxes are respectively fixed on the rear sides of the ditching discs, are symmetrically fixed on the stander and are in transmission connection with the rotating main shaft; and a bottom-tillage cutter shaft is fixed between the transmission boxes on two sides and is in transmission connection with the transmission boxes on two sides, and a plurality of bottom-tillage knives are uniformly arrayed onthe bottom-tillage cutter shaft, so that the ridging-smashing and bottom-tillage functions are switched, the growth of plants is promoted, the moisture loss is prevented, and the high yield of crops is promoted. The double-shaft powder-tillage bottom-tillage machine has two functions; when the rotary tillage knives are mounted on the main shaft, the layering ridging smashing is realized, and the loose tillage of upper and lower soil layers can be realized; and when the rotary tillage knives are not mounted on the main shaft, the bottom-tillage can be realized, so that the functional switchingand the two functions are realized.