The invention relates to a pneumatic plate element (1) consisting of a hollow body (3) that can be impinged upon with a pressure medium having overpressure p. Said hollow body is located between two pressure/tension elements (2) that are connected to one another by their ends and is made of a flexible membrane (9). When transversal load is exerted on the plate element (1) placed on two supports (17) with load force F, the top pressure/tension element (2, 7) is subjected to pressure and the bottom pressure/tension element (2, 8) is subjected to tension. Prestressed tension elements (4) placed at a distance a traverse in channels the hollow body (3) between the pressure/tension elements (2, 8). The tension elements (4) are prestressed by the hollow body (3) separating the tension elements (2). The connections (6) operate as fictitious fixed intermediate supports and stabilize the pressure/tension element (2, 7) submitted to pressure in order to prevent buckling. Two-dimensional plate elements (1) can be particularly used for building roofs of lightweight constructions.