Precision shaped masonry blocks each have four rabbets. The blocks are joined by toothed elements (42) of inserting element (4) that are inserted into two parallel rabbets on the upper touching surface. The inserting elements are subjects to only axial forces. The rabbets of upper block rows are placed on smooth parts (41) of the inserting element (4) which protrude from the lower block rows. A tool (6) is used to align the blocks. When the blocks are in position they are fixed by pressing the toothed parts (42) of the inserting element (4) in the rabbets (14), (24) and (34) on the frontal contact point of the blocks. On the straight part of the wall, basic blocks (1) are used. On the angular part of the wall or on the intersection of several wall the angular blocks (2) are used. These have built in cylinders (25) which serve as formwork for vertical pillars. On the floor level trough-like block (3) and (3') are used for formong horizontal armoured concrete girders.