The invention provides a second point grounding resistance and grounding position calculation method during generator rotor two point grounding. The method includes the steps that the grounding resistance and grounding position during generator rotor one point grounding are calculated; according to the grounding resistance and grounding position during generator rotor one point grounding, the grounding resistance and grounding position of the second point during generator rotor two point grounding are obtained through the following calculation formula. The grounding resistance and grounding position of the second point can be obtained directly just through rotor one point protection, the algorithm is suitable for various rotor grounding protection logics capable of calculating the grounding resistance and the grounding point position, generator rotor grounding protection is achieved, calculation is simple and reliable, the adaptability is high, and rotor fault location and checking efficiency are improved greatly. Based on injection type rotor grounding protection, the grounding resistance and grounding position of one point grounding are calculated, and while a calculation formulais derived, precision of the whole calculation result can be ensured.