Based on the analysis of multi-parameter coupling, which is based on ground source imbalance temperature limit, the building load characteristics and the heat transfer mechanism, this paper put forward an evaluation index, including the energy storage imbalance temperature limit, energy imbalance, and system invalidating indicator, and built the evaluation system on ground energy storage condition. Based on this evaluation system, by using the three-dimensional pipe-group model created by CFD software, a calculation method to accurately analyze the ground energy storage condition of ground source heat pump system was proposed. The result of calculation and analysis show that the evaluation system and calculation method reflect ground energy storage condition objectively and the ground source imbalance temperature limit can be concluded on the basis of the characteristics of practical projects in this method. The failure time of energy saving and efficiency can be predicted in the life cycle.