The changes of potato polyphenol oxidase relative activity, brightness, chromaticity and vitamin C content were inspected by comparing potato slice processed with infrared and hot water blanching inactivation process, respectively. The optimum technology parameters were obtained by using multivariate nonlinear fitting method and they are as follows: when the infrared intensity is 4.0 kW/m2 and the thickness of the slice is 3 mm，the processing time and vitamin C remaining content would be 2.5 min and 6.983 mg/(100g). When the blanching temperature is 100℃ with the same thickness of the slice，the processing time and the vitamin C remaining content would be 4.0 min and 7.068 mg/(100g). Compared with the traditional hot water blanching processing, the processing time can be decrease by 37.5% with infrared processing.