Abstract: This paper systematically measures the per capita grey water footprint in 31 provinces in the mainland of China during 2000-2014. Capital and labor factors which are most critical in production factors are first introduced into the research about driving effect of per capita grey water footprint, besides, traditional environmental efficiency factors and technical efficiency factors are coupled. Subsequently, the driving effect of the above factors on per capita grey water footprint is analyzed synthetically by using the extended Kaya identity and LMDI model. The results show that: 1) Nationwide, the biggest reduction of per capita grey water footprint comes from technical efficiency effect, the reduction effect of capital output has been improved in recent years, and the most increment effect is from capital deepening (the annual average value exceeds 52.29 m³ per capita). 2) The spatial distributions of the technical efficiency effect, the capital output effect and the capital deepening effect are all high in the northwest and low in the southeast; environmental efficiency and technical efficiency have greater decrement effect on the per capita grey water footprint in Hebei, Beijing, Tianjin and Shandong, and technological efficiency and capital output are more favorable for the reduction of per capita grey water footprint in other provinces; in addition, capital deepening can lead to significant increase in per capita grey water footprint in all provinces, and it causes the increment over 400 m³ per capita in Tibet.

Key words: driving effect, factor and efficiency, LMDI model, per capita grey water footprint