To provide a small-sized and inexpensive very short distance toss-up type absolute gravimeter.

This very sort distance toss-up type absolute gravimeter 100 has a vacuum container 110 laid on a ground face, a reference mirror 122 supported inside the vacuum container, a drop mirror 124 dropped inside the vacuum container, a toss-up device 180 for tossing up the drop mirror 124 by a fixed distance, an atomic clock 164 for specifying a time with high precision, an interferometer for measuring a position of the drop mirror 124 time-serially and capable of obtaining an interference waveform itself, and a computing part 166 for calculating a gravitational acceleration, based on the waveform provided by the interferometer and the time specified by the atomic clock 164.