The purpose of this paper is to urgently report the decline in groundwater levels at Thang Long Industrial Park (TLIP) in the area of Northwest Hanoi, Vietnam. The total pumping capacity in TLIP is 56,970 m³/day. According to the records of the observation well close to TLIP, groundwater levels have declined since 2008. The amount of decline was approximately 5.67m between 2008 and 2011. Lower levels appear in the dry season, particularly in March-April. In order to maintain sustainable use of groundwater in TLIP, one of the issues is to carry out an artificial recharge of groundwater using Kim Hoa Canal, of which water is supplied by the Ca Lo River.