The invention relates to a measurement system for the wireless and position-independent measurement of the temperature of the load of an oven with high accuracy using passive temperature probes. The measurement system for the wireless measurement of the temperature of food or workpieces in ovens has an interrogation unit located outside the oven chamber, one or more interrogation antennas located in the oven chamber and at least one passively operated temperature probe with a probe antenna and at least one temperature sensor designed as a resonator, said temperature probe being freely movable within the oven, characterized in that the temperature sensor has at least two resonances with different temperature coefficients of frequency, wherein the electrical equivalent circuit diagrams of the resonance elements differ only slightly from each other.