Abstract: Electrical Resistance Tomography (ERT) is a new measurement technique for detecting the distribution parameters of two-phase flow which is a on-line and intime method. It has many advantages and has been stressed by many researchers of different countries, it has developed very fast in the years. This paper first introduces the composition of ERT; then it reviews the research status of sensor structure, data acquisition system hardware circuit, the reconstruction algorithm, and applications of ERT; it points out the key problems that must be solved in the development of ERT; finally it prospects the tendency of development and application of ERT in the future.