Ultra-high sensitivity magnetic field measurement is of great scientific and economic significance. Precision measurement of physical quantities using atomic spin effect has become an important means in the field of experimental physics in recent years, among which spin-exchange relaxation free（SERF）atomic magnetometer has attracted much attention because of its ultra-high sensitivity. The alkali metal cell is the sensitive core of SERF atomic magnetometer, and the type of atomic source determines the limit of sensitivity. This paper summarized research results of the SERF atomic magnetometer in accordance with the alkali metal atoms source classification summary, analysis of the research methods, the research progress and the breakthrough obtained in practical application, the development requirement and challenges of SERF atomic magnetometer.