Scaffolding, comprising a U-section beam, which extends along a U-section beam longitudinal axis thereof and has an outwardly open U profile, and comprising at least one scaffolding floor, which is detachably fixed to the U profile and which has at an end one or more suspension hooks for suspension in the U profile, and comprising at least one anti-lift-out device (70.1, 70.2), which is detachably connected with the U-section beam and which includes a fastening device (71.1, 71.2) and an anti-lift-out body, wherein the U profile of the U-section beam has support limbs (33.1, 33.2) which are arranged parallel to one another and parallel to the longitudinal centre plane of the U profile and are connected together by a transverse wall and which have support edges (50.1, 50.2) for the laying-on of the suspension hook or the suspension hooks of the at least one scaffolding floor and wherein the suspension hook or hooks of the at least one scaffolding floor is or are detachably laid on at least one support edge (50.1, 50.2) of the support edges (50.1, 50.2), and wherein the U-section beam has a guiding and fastening groove, which is bounded by the transverse wall and is open in the direction of the support edges (50.1, 50.2) of the support limbs (33.1, 33.2) as well as towards the inner sides thereof and which extends in a transverse direction transversely to the support limbs (33.1, 33.2) and in a longitudinal direction transversely or perpendicularly to the transverse direction in the direction of its longitudinal axis and, with formation of a longitudinal slot, is bounded by groove engagement-behind webs (53.1, 53.2), which are arranged at a mutual spacing and along the inner sides of the two support limbs (33.1, 33.2) and extend respectively inwardly therefrom and which bound a locking space of the guiding and fastening groove, in which a locking body (74.1, 74.2) can be releasably arranged at several positions along the guiding and fastening groove, and wherein the fastening device (71.1, 71.2) of the anti-lift-out device (70.1, 70.2) comprises a fastening body (73.1, 73.2), the locking body (74.1, 74.2) and a securing body (75.1, 75.2), and wherein the fastening body (73.1, 73.2) extends in the direction of the fastening body longitudinal axis (76.1, 76.2) thereof transversely or perpendicularly to the anti-lift-out body, and wherein the securing body (75.1, 75.2) is arranged at the fastening body (73.1, 73.2) at a spacing (78.1, 78.2) from the locking body (74.1, 74.2), and wherein the locking body (74.1, 74.2) is fastened to the fastening body (73.1, 73.2) and extends in the direction of the locking body longitudinal axis (77.1, 77.2) thereof transversely or perpendicularly to the fastening body longitudinal axis (76.1, 76.2) of the fastening body (73.1, 73.2), and wherein the locking body (74.1, 74.2) is transferred into a locking setting (97.1, 97.2) in which it engages behind the groove engagement-behind webs (53.1, 53.2) of the guiding and fastening groove and in which it is releasably fastened in the locking space of the guiding and fastening groove, and wherein the locking body (74.1, 74.2) is rotatable by means of or by way of the fastening body (73.1, 73.2) about the fastening body longitudinal axis (76.1, 76.2) from its locking setting (97.1, 97.2) into an unlocking setting (98.1, 98.2) in which the locking body (74.1, 74.2) is movable by means of or by way of the fastening body (73.1, 73.2) in a direction transverse or perpendicular to the longitudinal axis of the guiding and fastening groove away from the transverse wall out of the guiding and fastening groove through the longitudinal slot, and wherein the anti-lift-out body has a passage opening (81.1, 81.2) through which the fastening body (73.1, 73.2) is inserted so as to be rotatable about the fastening body longitudinal axis (76.1, 76.2) thereof relative to the anti-lift-out body, and wherein the anti-lift-out body engages over the suspension hook or hooks, and wherein the anti-lift-out body by means of the securing body (75.1, 75.2) by way of the fastening body (73.1, 73.2) and the locking body (74.1, 74.2) secures the suspension hook or hooks against lifting out of the U profile in a direction transverse or perpendicular to the U section beam longitudinal axis, characterised in that the anti-lift-out body extending in the direction of the anti-lift-out body longitudinal axis thereof is a component of an anti-lift-out and support body comprising a support body (59.1, 59.2, 59.3) which is fixedly or rigidly connected with the anti-lift-out body and extends transversely or perpendicularly away from the anti-lift-out body up to its support body end (79.1, 79.2.1, 79.2.2, 79.2.3, 79.3) and which is supported by its support body end (79.1, 79.2.1, 79.2.2, 79.2.3, 79.3) on the transverse wall of the U-section beam and the passage opening (81.1, 81.2) of the anti-lift-out body is formed in such a way that the locking body (74.1, 74.2) is movable by means of or by way of the fastening body (73.1, 73.2) in the direction of the fastening body longitudinal axis (76.1, 76.2) thereof as well as transversely or perpendicularly to the longitudinal axis of the guiding and fastening groove through the passage opening (81.1, 81.2) of the anti-lift-out body.