The invention provides a low-loss material dielectric property measurement device adopting a split-cylinder resonator method. The low-loss material dielectric property measurement device adopting the split-cylinder resonator method comprises a base plate, a fixed cavity, a movable cavity, a supporting seat, a force moment handle, a lower guide rod, a precise linear bearing, an upper guide rod, a locking screw, a coaxial connector, a positioning pin, a connecting plate, a protective plate and a stop block. By means of the scheme, the theoretical advantage that the accuracy of low-loss material dielectric property measurement by means of the split-cylinder resonator method is high can be fully played. In addition, measured samples are simple in preparation and quick and convenient to measure. For different measured samples, clamping forces of two resonant cavities can be adjusted through the force moment handle, accordingly measurement distortion caused by improper clamping is decreased, and measurement accuracy is ensured. For the same samples, the clamping forces are constant, and consistency of measurement results can be ensured.