Surface tension is one of the most important physical chemistry parameters in material field. Many interface phenomena under microgravity attract scientists and need farther study. Sessile drop method is the main way to measure surface tension of melts, which works well on the earth. However, it is difficult to be used under microgravity environment. The paper expresses new cognition about measurement after thinking of the theory of surface tension, and discusses the difficulty of using sessile drop method under microgravity environment. This paper introduces levitation method to measure the surface tension, especially the electromagnetic levitation method, which avoids the error brought by vessel contacting. Under microgravity environment, the electromagnetic levitation method can improve the measurement precision.