For plate quenching on a roller quenching machine, heat transfer process is investigated. According to the practical online experiment of plate center temperature, average heat transfer coefficient under different conditions and temperature fields are analyzed by numerical simulation. The results show that, at the water temperature of 15 °C, the instantaneous maximum quenching cooling rate is 17.6 °C/s for the plate of 50 mm in thickness in roller quenching process. In the temperature range of 400-850 °C, the maximum is 12.1 °C/s. With the plate surface temperature decreasing, surface heat transfer coefficient increases at first, and reaches the maximum value of about 15000 W/(m2 · K), and then decreases. The calculated heat transfer coefficients are applied to analyze plate temperature field of different thicknesses, and the difference between the calculated and measured temperature is less than 5%. © 2013 Central Iron and Steel Research Institute.