As one of the energy storage technologies, borehole thermal energy storage (BTES) has lower heat storage efficiency and greater heat loss in the first few years, but has good application prospect due to its advantages. It is known that the performance of BTES influenced by many factors. Therefore, this study focus on design, operation and environmental impact parameters to investigate the influencing mechanism on BTES performance of these parameters over the entire input spacing. ANSYS-Workbench is used to build the simulation model and global sensitivity analysis Treed Gaussian Process method is employed to assess the relative importance of influencing factors and interaction among influencing factors. Sensitivity analysis result showed that spacing is the most critical factor influencing storage efficiency (SE) and temperature density (TD). Selection of spacing is very important for BTES to increase SE and make the storage of energy as dense as possible. Besides, soil thermal conductivity and depth are the dominant influencing factors on SE and TD, respectively. Moreover, the interactions among variables influencing SE are significant. Finally, intermittent operation mode is conductive to SE improvement. (C) 2019 The Authors. Published by Elsevier Ltd.