Provided is a tongue separation device including: a body unit including a contact surface fixing a tongue； a support unit arranged at one end portion of the body unit and supporting the body unit from outside a mouth； a tooth mounting unit arranged at one surface of the support unit adjacent to a first region of the body unit, mounting the teeth in a state where the body unit is inserted into the mouth, and including an upper surface mounting upper teeth among the teeth and a lower surface mounting lower teeth among the teeth； and a tongue position checking unit including an opening formed at the support unit to check a position of the tongue from outside the mouth, wherein a first portion of the contact surface of the body unit adjacent to the one end portion of the body unit is arranged over a virtual extension surface that passes through a center of the support unit and crosses between the upper surface and the lower surface of the tooth mounting unit, and a second portion of the contact surface of the body unit adjacent to the other end portion of the body unit is arranged under the virtual extension surface.
