Taking an example of the straight line type parallel well in Xi'an groundwater source heat pump, the impact scope of seepage field and the corresponding function of the impact scope of seepage field, safe distance and well spacing are respectively analyzed by analytic method and numerical simulation method. The results showed that seepage impact scope and safe distance have a positive correlation with well distance when hydrogeological parameters and pumping parameters are definite. In designing wells layout of groundwater source heat pump, the impact of pumping systems on seepage and surrounding buildings should be taken into consideration , in order to reasonably plan the water source heat pump well area and optimize the pumping well spacing.