The purpose of the present invention is to install an economizer having a sufficient internal volume in a compact turbo refrigeration apparatus specifically using a low-pressure refrigerant, and reduce refrigerant pressure loss and enhance efficiency in the turbo refrigeration apparatus. The turbo refrigeration apparatus according to the present invention comprises: a turbo compressor which compresses a refrigerant; a condenser which condenses the compressed refrigerant; a control valve which causes the condensed refrigerant to expand; an evaporator which causes the expanded refrigerant to evaporate; and an economizer which is installed in such a manner as to be sandwiched between the condenser and the evaporator, and separates the refrigerant expanded by the control valve into gas and liquid. The economizer is installed adjacent to a curved wall, having a drum shell shape, of the condenser and/or the evaporator, the curved wall being shared with the structural wall of the economizer. The economizer has a height (H) greater than the maximum width (W) thereof when viewed in the longitudinal direction thereof.