The invention relates to a device for measuring at least one parameter of the intake air mass flow of an internal combustion engine. Fluid particles contained in the line act on a measuring element and influence a characteristic curve behavior of the measuring element used to determine parameters of the flowing medium. In order to reduce the action of fluid on the measuring element, the measuring element is disposed in a line or a tubular body, downstream of a protective screen, which deflects the medium flow and deflects the fluid particles. Downstream of the protective screen, longitudinal ribs, a suction opening, or a turbulence generator reduce the release of uncontrolled eddies.