An information processing system including an image inputting apparatus including a first certification control unit that sends a certification request, in which a public key certificate read from a recording medium is designated, to a certification apparatus connected with the image inputting apparatus through a network and receives proof data indicating that certification is completed from the certification apparatus, a delegating unit that delegates the proof data to the information processing apparatus, which is connected with the image inputting apparatus through the network, and a sending unit that sends a delivery request for delivering image data input by the image inputting apparatus to the information processing apparatus, and an information processing apparatus which acquires an access right to a delivery destination of the image data using the proof data delegated by the delegating unit.