Abstract: Quanta 400 scanning electron microscope is a large scale precision instrument, and various equipment faults would occur occasionally during the operation. The good daily maintenance and management of the scanning electron microscope can improve the service life of the components and parts. Some common faults and corresponding elimination methods of the scanning electron microscope were summarized, including the cooling circulatory system faults and vacuum system faults. Additionally, maintenance measures of the easy wear parts were also suggested, including the maintenance of filament and the objective aperture.