A data processing device according to the present application includes a reception unit, a first memory unit, a second memory unit, and a storage unit. The reception unit receives user information relating to a user using a user terminal by being triggered upon an access of the user terminal to an information providing device. The first memory unit stores the user information that is received by the reception unit. The storage unit stores the user information in a management area of a second memory unit that is different for each information providing device that is a trigger for reception of the user information stored in the first memory unit.