To provide a cleaning designing and supporting method enabling even a person having no expert knowledge not only to adapt a calculation formula for cleaning or the design of a cleaning apparatus, but also to easily achieve the design of cleaning conditions and the cleaning apparatus on the basis of the adaptation.

The cleaning designing and supporting method is equipped with a step or inputting data for a cleaning design on the side of a client computer, a step for transmitting the data for the inputted cleaning design from the client computer to a server computer, a step for receiving the data for the transmitted cleaning design by the server computer, a step for performing calculation for the cleaning design on the basis of the data for the received cleaning design, a step for transmitting the result of the performed calculation from the server computer to the client computer and a step for displaying the result of the transmitted calculation on the side of the client computer.