Abstract: A method of producing slab-like concrete elements having mutually parallel sides and containing one or more filling bodies wherein a part of the element which contains one or more filling bodies is cast in a first manufacturing stage and allowed to harden, and wherein the hardened part is turned upside down and lowered into a mould which contains fresh concrete, in a second manufacturing stage and the fresh concrete is allowed to harden. In the first manufacturing stage the concrete is poured into the mould to a level such that the upwardly facing side of each filling body will be free from concrete; in that the free surface of each filling body has provided therein recesses whose combined volumes correspond to the variation in the amount of concrete used in the second manufacturing stage; and in that in the second manufacturing stage the first part is lowered into the mould containing fresh concrete to a level at which the produced concrete element has a nominal thickness.