The invention relates to a bottom-cover type planar bearing special for a conical sand making machine, which not only has an oil guiding function, but also has the function of a planar bearing. The lateral part of a cover cavity of a bottom cover is provided with an oil hole; a plurality of layers of superposed boards are arranged in the cover cavity; and oil films are arranged between every two layers of superposed boards. The bottom-cover type planar bearing special for the conical sand making machine has the advantages of the function of a shaft cap, the oil guiding function, the function of the planar bearing, and novel, unique, simple and practical structural design.