The invention relates to a soil sampler which comprises a main body and a soil sampling knife, wherein the main body comprises a barrel body and a base; convex pins are symmetrically arranged on two sides of the lower end of the barrel body; screw holes are formed in the convex pins; screw holes with the same sizes are also formed in the base; the barrel body is fixedly connected with the base in a manner of enabling screws to penetrate through the screw holes; the soil sampling knife with a matched size is arranged in the barrel body; a knife handle is arranged at the upper end of the soil sampling knife; the soil sampling knife comprises a soil sampling knife with a cutting edge and a soil sampling knife without the cutting edge; and the soil sampling knife with the cutting edge is positioned at the lower end of the soil sampling knife without the cutting edge. The soil sampler has the beneficial effects of simple structure, simple equipment operation, easiness for processing and manufacturing, convenience in carrying and successful soil insertion; the operation for digging the section of soil is eliminated; furthermore, undisturbed soil structures at different depths can be sampled at a time, and the original structure of the soil is not damaged; and the soil sampler is large in sampling amount.