To provide a manufacturing method and a manufacturing device for a gradation filter which enable manufacture of the gradation filter at low cost in a short time.

An image generating means comprising a PC 3 and image processing software generates image data of a gradation pattern (step S1). According to the image data, a gradation generating means comprising printing equipment 5 prints the gradation pattern on a filmy transparent substrate to form a gradation pattern sheet 7 (step S2). The gradation pattern sheet is cut in conformity with filter glasses 9a and 9b into a cut piece 7 (gradation pattern sheet) (step S3). The filter glasses 9a and 9b are preferably formed in advance (step S4). The cut piece 7 is sandwiched between the filter glasses 9a and 9b to complete the gradation filter 1 (step S5).