Abstract: LCR-G Gravimeter, Which is widely used in the field of geodetic survey andseismic prospecting, is a kind of high precision gravimeter.We usually do experiment with some arbitrary disturbs in laboratory to test its funciton.Since the test time is short, this kind experiment has its limitation in long-term function study.Thus, no papers on this problem have been published till present.Based on the character of field fixing site resurvey for gravity, we studied the longterm dynamic function for LCR-G gravimeter with observed data.The conclusion is the combining effect of the first and second aging for spring of the gravimeter with the variation of temperature in season is the main reason for the drift of the instrument.The first aging, which is unitary, is the dominant factor.The second aging has commonness.The temperature variation with season has periodical feature.