An NMR measurement apparatus adopts a circulation flow scheme using a sample solution containing a high molecular compound representing a measuring object and a low molecular compound solution containing a low molecular compound representing a ligand. The measurement apparatus comprises a mixing filter 32 for mixing the sample solution and the low molecular compound solution, a separation filter 34 for performing separation therebetween, a flow channel 1 through which the sample solution drained out of the separation filter 34 is injected to the mixing filter 32, a flow channel 2 through which the low molecular compound solution drained out of the separation filter 34 is injected to the mixing filter 32, and a flow channel 3 through which the mixture solution drained out of the mixing filter 32 is injected to the separation filter 34 by way of a reservoir 10.