Abstract:This paper introduces the working modes of ML-1 frequency-stabilized laser. The results of single mode and two modes measurements are compared with those of the FG5X absolute gravimeter. We show that the working modes of ML-1 laser can effectively reduce the influence of temperature drift and time drift on absolute gravity observation. The red/blue separation indicates the laser drift. When the red/blue separation is large, it indicates that there is a large drift in the frequency-stabilized laser, which needs calibration.