Provided is a substrate treating apparatus. The substrate treating apparatus according to embodiments of the present invention may include a cleaning chamber cleaning foreign objects on a substrate, and a recycling unit recycling by recovering a mixed solution including a first chemical and a second chemical used in cleaning of the substrate, wherein the recycling unit includes a separation unit separating the mixed solution recovered from the cleaning chamber, a recovery line connecting the separation unit and the cleaning chamber and allowing the mixed solution to flow into the separation unit, a decompression line having one end connected to the separation unit and exhausting the mixed solution evaporated from the separation unit, and a decompression unit installed in the decompression line and reducing pressure in the separation unit.