The change of the confined aquifer level reflects the pore pressure change，and the pore pressure change of the aquifer is closely related to the aquifer pressure． The paper used the tidal response of the well water level data in the North China region，calculated the tidal factor of each well and extracted the effective water trend information． Then we inverted the volumetric strains of existing confined aquifer well in the North China region，and drew the contour maps on the basis of half a year from 2009 to 2012． Ｒesults show that it can reflect the deep state of stress and strain to a certain extent in the North China region．