River water quality is one of the important conditions must be considered when river water source heat pump is used. It is also the key factor of efficiency of river water source heat pump. Based on analysis of the water quality factors which influence the river water source heat pump heat exchanger fouling, the main quality indicators and value are conformed. Using fuzzy comprehensive evaluation method and the actual monitoring data, quality classification of river water which is the source of water source heat pump is analyzed. For the difficulty of multiple indicators which need to detect and meet the related national standard in practical engineering application, the definition of scaling potential value is put forward. As the water quality comprehensive evaluation index of water source heat pump, the scaling potential value not only can consider the influence of the main water quality parameters on water source heat pump heat exchanger fouling, but also can conveniently and quickly provide direct basis for water quality judgment and system selection in the engineering application.