The invention discloses a device for releasing a falling body prism of an absolute gravimeter, comprising a vacuum cabin, a lower bracket plate, a linear motor, an upper bracket plate, a latch chamber, an electromagnet, a spring, a steel ball, a hanging nail, the falling body prism, a guide rod, a buffer spring, a support vehicle and a perspective window mirror, wherein the electromagnet and the spring are contained in the latch chamber; the steel ball is arranged at the inner bottom of the latch chamber; the bottom of the latch chamber is a concave slope and an opening is arranged in the middle of the bottom of the latch chamber; the spring is clamped between the electromagnet and the steel ball; and the steel ball is in contact with the bottom of the latch chamber. The latch chamber, the spring, the steel ball and the electromagnets are used as clamps so as to play roles of clamping and releasing the falling body prism of the gravimeter; and the device is good in anti-fatigue characteristic, stable and rapid in releasing, durable, free of great interference of mechanical movement in the falling process of the falling body prism and beneficial to the high-precision gravity measurement.