The measuring system is inserted into the course of a process line and is used to record at least one measurement variable of a medium flowing in the process line. For this purpose, it comprises a measuring sensor having a measuring tube, which is used to guide medium to be measured, and having a sensor arrangement which has at least one sensor element, which primarily reacts to the measurement variable to be recorded, and uses the at least one sensor element to provide at least one measurement signal which is influenced by the measurement variable. The measuring system also comprises measuring electronics which communicate with the measuring sensor and use the at least one measurement signal to at least occasionally generate at least one measured value which instantaneously represents the measurement variable. In the measuring system according to the invention, the measuring tube has a smaller flow cross section than an intake segment of the process line that is connected to the measuring system on the inlet side. The measuring system therefore also comprises a flow conditioner which is arranged on the inlet side of the measuring tube, mediates between the latter and the intake segment of the process line and has a lumen which tapers towards the measuring tube and through which the medium flows during operation. The flow conditioner has at least two inner edges which are arranged upstream of the outlet end of said flow conditioner, project into the lumen of the flow conditioner and against each of which medium flows during operation, which medium is guided inside the flowconditioner. A first guide surface of the flow conditioner also extends between the first inner edge and the second inner edge. In addition, the second inner edge bounds a second guide surface of theflow conditioner, which second guide surface is used to guide medium flowing in the flow conditioner and extends in the direction of the outlet end of the flow conditioner.