Abstract: For removing a photoresist formed on a semiconductor wafer by using an ozone-dissolved water, until just before a low temperature ozone-dissolved water generated by an ozone-dissolved water generator is discharged from a discharge nozzle onto a semiconductor wafer placed on a stage, the semiconductor wafer is heated to a predetermined temperature which is higher than ordinary temperatures. When the low temperature ozone-dissolved water having a high concentration of ozone is discharged onto the semiconductor wafer, the temperature of the ozone-dissolved water elevates upon the instant. Thus, the photoresist formed on the semiconductor wafer can be removed by a high temperature, high ozone concentration, ozone-dissolved water.