A new FE modeling method of hot ring rolling was presented by solving key technologies such as contact and heat boundary conditions, motion control over guide rolls, and mass scaling. The method has the following features: 1) the elastic-plastic dynamic explicit approach instead of the static implicit approach is adopted to solve the process so as to greatly improve computational efficiency without sacrificing computational accuracy; 2) the coupled thermal-mechanical effect is considered as opposed to the conventional isothermal assumption, which is more practical; 3) in contrast to the simplified 2D or local 3D ring model, the full 3D ring is modeled to simulate the process. Based on the FE modeling method, two cases of hot plain ring rolling are simulated in the FEA software ABAQUS/Explicit. The simulation results are compared with the experimental measurements and the good agreement between them is observed regarding the material flow and the temperature distribution of the ring.