The invention relates to a sensor of a Coriolis meter for measuring the mass flow or the density of a medium flowing through a pipe, said sensor comprising: at least one measuring tube for conducting the medium, each having an inlet and an outlet; at least one exciter for exciting measuring tube oscillations; at least two sensors for detecting measuring tube oscillations; a support body for holding the measuring tube. The sensor has an RFID temperature sensor which is designed to determine a temperature of the measuring tube, the sensor having an RF transceiver which is designed to read out the temperature sensor.