PURPOSE: To raise the strength of slope by a method in which a wire netting is laid on the slope, blocks are fixed to the topside of the netting by mutually facing their peripheral sides, and a water-proof coating material melted by heating is applied onto the blocks.

CONSTITUTION: Slope 1 is formed by cutting or banking, and a wire netting 2 is laid on the slope by fixing its upper and lower ends to the ground by anchors 3. Rectangular concrete blocks 4 are orderly set from the lower end of the slope 1 by contacting their peripheral sides 5 and fixed by wires, etc. Asphalt 6 as a coating material is uniformly supplied onto the blocks 4, melted by heating by means of a gas burner 7, and tightly packed into the recessions of the blocks 4 and hardened. The working time can thus be shortened and the run-off of sediment can be prevented.