PURPOSE: To obtain an apparatus for forming a ridge between rice field with a high efficiency by providing a slope forming blade and a top face forming blade each having cutting blade to a bulldozer.

CONSTITUTION: The turning angle of the support frame 20 of a ridge former 2 is adjusted so as to match the sideward inside end of the cutting edge 104 of a slope forming blade 14 with the lower end (basal face 160) of the soil 158 of a ridge. Then, a handle 124 is operated to set the cutting edge 108 of a top face forming blade 16 horizontally, and the bulldozer 8 is set on the side of the ridge former 2. When advancing the bulldozer 8 along the longitudinal direction of the soil 158 of the ridge, a ridge having an inclined face 162 and a top face 164 can be formed by the cutting action of the blades 14 and 16 and the pressing action of a pressing shoe.