A sample analyzer according to an embodiment includes a magnetic field applier configured to apply a magnetic field to a cartridge containing a sample and magnetic particles which bond an object to be detected in the sample; a measurer configured to measure the magnetic particles in the cartridge; and an analyzing processor configured to analyze and process a result of a measurement by the measurer. In addition, the magnetic field applier includes an electromagnet disposed on a first side of the cartridge; a magnetic member configured to be magnetized by the electromagnet; and a moving actuator configured to move the magnetic member.