The present invention relates to a heating device for one or more components of an extracorporeal circuit of a blood treatment device, in particular of a dialyzer, an adsorber or a filter, wherein the heating device has at least one reception region for the named component and at least one heating element for heating the component located in the receiver, wherein the heating device has a plurality of layers, with at least one layer being a flexible layer or elastically deformable layer.
