The measuring device is arranged to measure at least one property of a moving web. The measuring device includes at least one measuring head with at least one measuring element arranged in a flexible membrane that surrounds the measuring element and is arranged in connection with the measuring head such that the measuring element is movable by means of the flexible membrane perpendicularly to the moving web. The turning effect, which is caused by the pressure of the air conveyed with the moving web, and directed in the travel direction of the web at least in front of the measuring element on the web side of the flexible membrane, and turns the measuring element, is prevented by at least partly changing the amount and/or flow direction of the air conveyed with the web moving to the measuring element.