A cyclone type liquid-vapor separator for separating vapors from treatment liquid introduced thereinto, discharging the separated vapors to the upper portion thereof, and discharging concentrated treatment liquid to the lower portion thereof, the liquid-vapor separator comprising: a chamber comprising: an internal space wherein the treatment liquid introduced into the internal space is depressurized and evaporated; a vapor outlet formed on a top of the chamber and through which vapors generated through the evaporation is discharged; and a concentrated liquid outlet formed on a bottom of the chamber and through which the concentrated treatment liquid is discharged; an inlet part coupled to a side surface of the chamber in a tangent line direction of an inner peripheral surface of the chamber, the treatment liquid introduced into the chamber is turned in the form of vortexes along the inner peripheral surface of the chamber; and at least one partition wall disposed in an area between the inlet part 120 and the vapor outlet of the internal space of the chamber and protruding from the inner peripheral wall of the chamber to prevent mist contained in the vapors from moving upwardly; wherein the inlet part comprises a guide part disposed extendedly by a section along the inner peripheral surface of the chamber from a connected portion to the side surface of the chamber and configured to guide a rotation of the treatment liquid introduced through the inlet part; wherein the guide part comprises a pipe passing through the inlet part, the pipe extendedly inserted into the chamber, and being fastened to the inner peripheral surface of the chamber along the inner peripheral surface of the chamber; wherein the pipe of the inlet part, which is passed through the chamber and extendedly inserted into the chamber, is open on a top portion of the pipe; characterized in that the guide part extends along the inner peripheral surface of the chamber at a constant level with respect to gravity. an internal space wherein the treatment liquid introduced into the internal space is depressurized and evaporated; a vapor outlet formed on a top of the chamber and through which vapors generated through the evaporation is discharged; and a concentrated liquid outlet formed on a bottom of the chamber and through which the concentrated treatment liquid is discharged; an inlet part coupled to a side surface of the chamber in a tangent line direction of an inner peripheral surface of the chamber, the treatment liquid introduced into the chamber is turned in the form of vortexes along the inner peripheral surface of the chamber; and at least one partition wall disposed in an area between the inlet part 120 and the vapor outlet of the internal space of the chamber and protruding from the inner peripheral wall of the chamber to prevent mist contained in the vapors from moving upwardly; wherein the inlet part comprises a guide part disposed extendedly by a section along the inner peripheral surface of the chamber from a connected portion to the side surface of the chamber and configured to guide a rotation of the treatment liquid introduced through the inlet part; wherein the guide part comprises a pipe passing through the inlet part, the pipe extendedly inserted into the chamber, and being fastened to the inner peripheral surface of the chamber along the inner peripheral surface of the chamber; wherein the pipe of the inlet part, which is passed through the chamber and extendedly inserted into the chamber, is open on a top portion of the pipe; characterized in that the guide part extends along the inner peripheral surface of the chamber at a constant level with respect to gravity.