Abstract: In this paper, the characteristics of data from digitized observation and correlation of change of underground water level and a tmo spheric pressure and terrestrial heat are analyzed. The results show that the data of digitized observation on underground water level, including their variation tendency, effects of atmospheric pressure and tidal, are identical with those from simulated observation. Theatmospheric pressure coefficient of data from digitized observation on underground water level is presented, atmospheric pressure coefficient of minute value on underground water level is 7. 3 mm/hpa, hour value is 7. 4 mm/hpa and daily average is 7. 1 mm/hpa. Tidal factor of M₂ wave is 0. 8011 from digitized underground water level, and its relativeerror is 0. 037 7. Terrestrial heat variation tendency is identical with underground water level from digitized observation.

Key words: Digitization, Underground water level, Atm ospheric pressure effect, Tidal effect