The present invention discloses an extended-type subsoiling smash-ridging machine, comprising a machine body, a smash-ridging device, a connection device, a ditching device, a flattening device and a straw returning device, wherein the smash-ridging device comprises a smash-ridging box comprising a bottom plate, side plates and a top plate, lower bearing seats are mounted in the bottom plate, rib plates are welded between the lower bearing seats, lubricating oil passages are formed between rib plates and the bottom plate, an upper bearing seats are mounted on the top plate and the length of each lower bearing seat is larger than that of each upper bearing seat. By adopting the structure of the present invention, the strength of the lower bearing seats can be improved so as to facilitate the mounting of more bearing where the stress is large and less bearings where the stress is small, thereby both improving the rigidity and transmission stability of a transmission shaft and reducing the cost； the welding of the rib plates is facilitated, it is ensured that lubricating oil smoothly flows within the smash-ridging box and the lubricating effect is improved.
