Abstract: The composite assembly of the steel structure for lifting equipment comprised of the lifting system, into which the lower parts of vertically connected pillars connected to one another by cross-beams are fixed, with a levelling lifting system comprised of lifting plates (11) that are anchored into a concrete recess using chemical bonds via openings (15), with the structure levelling system comprising an adjusting screw (14), adjusting load-bearing nut (12), and safety nut (13), where the adjusting screw (14) passes through the opening in the lifting plate (10) welded onto the lower part of the lowermost pillar (1) of the structure. The vertical connections (3) of individual pillars (1), on the inner sides of both ends fitted with sets of openings mutually arranged at the angle of 90 degrees, are realized by inner connecting pieces (18) with fixed nuts (21), attached by Allen head screws (20) with safety washers having high resistance to spontaneous releasing due to vibrations via a set of openings.