To determine the effect of coagulation time and temperature on coagulation process of soymilk and develop a method to online evaluate soymilk gel’s qualities nondestructively, electrical impedance spectroscopy (EIS) and rheological measurement (elastic modulus G′ and viscous modulus G″) were employed to analyze the coagulation process. Phase angle of soymilk mixture increased drastically at low frequencies and then gradually reached around zero at high frequencies in each tested time course, and 10kHz was chosen to evaluate soymilk coagulation process as an optimum frequency. Normalized volume resistivity at 10kHz initially increased sharply and then gradually approached to an equilibrium state for each temperature course. The similar tendency was observed for rheological properties during soymilk coagulation process. Electrical impedance spectroscopy measurement was useful in determination of the endpoint of soymilk coagulation process. The coagulation process of soymilk was divided into two stages which were considered as two successive first-order reactions. The activation energy values calculated by volume resistivity, elastic modulus and viscous modulus were 17.82, 112.90 and 53.72kJ/mol, respectively. The rheological properties were affected more greatly by coagulation temperature than EIS properties. Good agreements between volume resistivity and rheological properties were ascertained by the linearity of plot at all coagulation temperatures. Therefore, electrical impedance spectroscopy measurement can provide a method for determining the endpoint of soymilk coagulation process, which was also a simple, fast and realtime approach for monitoring the rheological properties of soymilk gel.