A spacing knitted fabric has a first and a second flat knitted fabric layer that are connected to each other by incorporated spacing threads. The first knitted fabric layer has mesh-forming loop threads made from thermoplastic plastic and non-mesh-forming additional threads made of thermoplastic plastic. In the first knitted fabric layer, only the additional threads are at least partially melted and due to the at least partial melting, causing a reinforcement of the first knitted fabric layer.