Truss support system for construction of a support construction, in particular in combination with existing structural elements of a framework system, having at least one three-dimensional truss girder device with a longitudinal direction (x), transverse direction (y) and vertical direction (z), which has continuous top chords and bottom chords, wherein the top/bottom chords (12, 14), as seen in a cross section, are arranged at the corner points of an imaginary triangle or rectangle, in particular has two top chords extending in the longitudinal direction (x) and spaced apart parallel to one another in the transverse direction (y) and two bottom chords extending in the longitudinal direction (x) and spaced apart parallel to one another in the transverse direction (y), which bottom chords are arranged spaced apart from the top chords so as to be parallel thereof in the vertical direction (z), - diagonals and posts which are connected/welded between a top chord and a bottom chord and in each case form a planar (x, z) truss construction with the top chord and the bottom chord, - transverse diagonals and transverse posts which are connected/welded between two top chords or bottom chords and in each case form a planar (x, y) truss construction with the top chords or the bottom chords, - wherein connected/welded to at least one top chord or bottom chord, in each case at its two face end regions, is a connector unit (40.1, 40.2) for connection of in each case one corresponding connector unit (40.2) of a further truss girder device for forming a continuous truss support system, wherein - the transverse posts are formed as rectangular- or square-tube hollow profiles, which form at the outside a planar (x, y) bearing surface or connection surface, - each connector unit (40.1, 40.2) has a connector connection unit, in particular a connector unit cutout, for connection of adaptor units for connection of further components, such as support profiles, framework posts or the like, to the adaptor unit, - characterized in that - at least one, in particular multiple, adaptor unit(s) extending in the transverse direction (y) is/are provided as further system parts for connection of further components, such as support profiles, framework posts or the like, to the adaptor unit, wherein the adaptor unit has a baseplate and two webs which extend at right angles to the baseplate and which are connected so as to be spaced apart parallel to one another and whose internal spacing corresponds substantially to the cross-sectional width of the transverse post, and in that the transverse posts have connection units, in particular connection cutouts, for connection of the one, or the multiple, adaptor unit(s) extending in the transverse direction (y). - diagonals and posts which are connected/welded between a top chord and a bottom chord and in each case form a planar (x, z) truss construction with the top chord and the bottom chord, - transverse diagonals and transverse posts which are connected/welded between two top chords or bottom chords and in each case form a planar (x, y) truss construction with the top chords or the bottom chords, - wherein connected/welded to at least one top chord or bottom chord, in each case at its two face end regions, is a connector unit (40.1, 40.2) for connection of in each case one corresponding connector unit (40.2) of a further truss girder device for forming a continuous truss support system, wherein - the transverse posts are formed as rectangular- or square-tube hollow profiles, which form at the outside a planar (x, y) bearing surface or connection surface, - each connector unit (40.1, 40.2) has a connector connection unit, in particular a connector unit cutout, for connection of adaptor units for connection of further components, such as support profiles, framework posts or the like, to the adaptor unit, - characterized in that - at least one, in particular multiple, adaptor unit(s) extending in the transverse direction (y) is/are provided as further system parts for connection of further components, such as support profiles, framework posts or the like, to the adaptor unit, wherein the adaptor unit has a baseplate and two webs which extend at right angles to the baseplate and which are connected so as to be spaced apart parallel to one another and whose internal spacing corresponds substantially to the cross-sectional width of the transverse post, and