There is provided a nuclear magnetic resonance probe in which the loss caused by a high frequency cable between a probe coil and a preamplifier is reduced and the sensitivity of an NMR signal is improved. A changeover switch for NMR probe is divided into a switch part including switch elements and a filter part for filtering a switch control signal and an RF transmission signal. The switch part is disposed in a probe body inserted in a magnet of the probe. The filter part is disposed near a measurement apparatus located outside the probe. As for the switch part, a section structure of thickness and width is reduced in conformity with a narrow and slender shape of the probe body. The length of a high frequency cable between the probe coil and the preamplifier is shortened remarkably, and consequently the loss can be reduced.