It eliminates harmful effects of electromagnetic fields and electromagnetic waves, it consists of an outer covering enveloping arranged mattress layers formed from natural or synthetic latex or another type of natural and/or synthetic foam, optionally containing various types of springs as a support core. Said mattress contains at minimum one layer (3) of a material for screening off electromagnetic waves and/or electromagnetic fields, wherein said material forms its inner layer and/or outer layer. The mattress may be provided with a conductive construction (7) of an extension consisting of a horizontal and vertical portion, wherein the horizontal portion of the conductive construction (7) of the extension is arranged at minimum in two edges of one horizontal surface of the mattress, the vertical portion of the conductive construction (7) of the extension is attached to for insertion, laying, gripping or attaching the layer (3) of the material for screening off electromagnetic waves and/or electromagnetic fields surrounding the lying surface of the mattress.