To eliminate the use of bar arrangement work and temporary frame, make it possible to construct a retaining wall with specific strength in optional size in a short period of time and, at the same time to enable the great reduction of a construction cost thereof.

A vertical bearing surface section 1 constituted of a plurality of vertical steel materials 1A and 2A, horizontal steel materials and flat plates 1C and 2C spread and fixed over all areas between the vertical and horizontal steel materials and an inclined bearing surface section 2 are connected with a plurality of joint steel materials 3A-3C to fix to construct a unit-type retaining wall able to stand alone with high strength. An optional number of unit-type retaining walls able to stand alone are arranged and are connected to each other, and the retaining wall in optional size can be constructed by placing concrete between both bearing surfaces 1 and 2.