To obtain a stable and high separation capacity and separation efficiency in gravity separation of granule, by the single gravity separation, or by the combination of the gravity separation with electrostatic separation or particle size separation, by improving carrying out of the granule by air current.

In this gravity separating apparatus, air is supplied from a fluidizing air supply port 8, a vibrator 3 causes vibration, the granule A supplied into a gravity separating vessel 2a from a granule charging port 1 is dispersed and horizontally moved by vibration, granule of small gravity is moved and floated to an upper part of the granule layer to discharge it from a first discharge port 7a, and granule of large gravity is discharged from a second discharge port 13a. An air suction port 6 is formed at the upper part of the gravity separating vessel 2a, and an air sucking means is provided for sucking the inner air from the first discharge port 7a and discharging it.