The invention relates to a leakage prevention and stoppage tool for a loess layer and a using method of the leakage prevention and stoppage tool. The leakage prevention and stoppage tool at least comprises a pipe body and further comprises a rubber cylinder assembly and a sliding sleeve which are sequentially arranged on the pipe body in a sleeving mode from top to bottom; and an upper steel ringand a lower steel ring are arranged at the two ends of the rubber cylinder assembly correspondingly, the upper steel ring is fixed to the upper part of the pipe body, a shear pin is arranged between the lower steel ring and the lower part of the pipe body, when the lower pressure is greater than the bearing capacity of the shear pin, the shear pin is sheared off, the sliding sleeve moves upwards,and thus the sliding sleeve is extruded axially. During using, the leakage stoppage tool is connected with a guide pipe string entering a well to be lowered into a loess borehole, after the guide pipestring reaches the well bottom, the sliding sleeve makes contact with the well bottom, guide pipes downwards press the sliding sleeve through the self weight, the shear pin is sheared off, and the guide pipe string continues moving downwards to extrude a rubber cylinder; and the rubber cylinder is compressed in the axial direction and expanded in the radial direction to make contact with the wellwall so as to be sealed. According to the using method, an annulus between the guide pipe string and the borehole in the loess layer is reliably packed and blocked at the well bottom, so that duringsubsequent drilling, circulating drilling fluid does not make contact with the loess layer, and the leakage prevention and stoppage effects are achieved.