The invention relates to a separation device, in particular to a solid-liquid-gas separation device by using the centrifugal separation principle. The device comprises a shell and a revolving shaft and a revolving drum arranged in the shell, wherein a mixed liquid inlet, a heavy phase outlet, a liquid outlet and a gas phase outlet are arranged on the shell; the revolving shaft penetrates through the upper end and the lower end of the shell and is rotatably connected with the shell, and the revolving shaft is arranged in the revolving drum. The revolving shaft and the revolving drum are fixedly connected through an axially arranged guide vane, wherein the revolving drum is cylindrical and has an upper opening and a lower opening; the revolving shaft is hollow, a baffle plate is fixed on anaxial wall of the revolving shaft adjacent to the upper opening of the revolving drum, a sealing device is arranged between the baffle plate and the shell, an gas cavity is formed at the top of the shell, and the air cavity is communicated with the gas phase outlet; the axial wall of the revolving shaft located above the baffle plate is provided with a gas outlet hole, the gas outlet hole is communicated with the gas cavity, and the axial wall of the revolving shaft located below the baffle plate is provided with a light phase collecting hole; a gas-liquid separator is fixed in a cavity of the revolving shaft, and the gas-liquid separator is located between the gas outlet hole and the light phase collecting hole; and an opening at the bottom of the revolving shaft is communicated with theliquid outlet. The separation device can be used for accurately separating solid-liquid, liquid-liquid or gas-liquid two phases or solid-liquid-gas three phases with different densities.