PROBLEM TO BE SOLVED: To provide a quantifying device and a measuring method of magnetic attraction, which grasp the behavior of collecting magnetic particles contained in a sample so as to find conditions of efficiently collecting the magnetic particles.SOLUTION: The device for quantifying magnetic attraction includes: a container 11 storing a liquid or powder sample 5 containing magnetic particles; a stage 10 on which the container 11 is installed; agitation means agitating the sample 5; an attraction unit 13 collecting the magnetic particles by magnetic force; and detection means 24 which detects a state of collecting the magnetic particles and which quantifies the magnetic particles.