To analyze the effects of the rotor eccentricity on the unbalanced current of the large salient-pole synchronous generator main protection， a model combining finite element method（FEM） with multi-loop method is proposed. This method can be divided into two parts: one is the solution of the voltage equations which express the generator external characteristics， and the other is the calculation of the electromagnetic parameters which present the internal characteristics. A multi-loop model regarding the stator branch as basic loop with eccentricity is set up and the electromagnetic parameters of the model are calculated using 2D FEM. The eccentricity ratio is varied on a 3 kW， 12-pole salient-pole synchronous generator under no-load operation and under three-phase symmetrical resistance load. Simulation and experimental results coincide each other， which validates that the analysis method can be used to simulate the rotor eccentricity for the salient-pole synchronous generator.