Abstract: This paper introduces a method of making ray exposure curve by using the EXCEL with pure formula method, and it does not need any language environment support. As long as the exposure is carried out according to the program prompt, and the measured blackness data is input into the corresponding table, the spreadsheet will use formula interpolation calculation instead of manually drawing D-T curve and will determine the thickness value according to the curve, and then according to the thickness value, the exposure curve can be generated immediately in the form of chart, which can greatly reduce the workload of intermediate drawing, chart checking and final drawing. It is convenient, fast, neat and accurate.