An approval device includes a storage circuit, a document acquiring circuit, an imaging circuit, a face recognition circuit, an approval circuit and an editing circuit. The storage circuit stores a face image database, the face image database registering face image data of at least one user to be an approver for approving a document. The document acquiring circuit acquires the document. The imaging circuit images a face of the approver for approving the document. The face recognition circuit analyzes an imaged face image of the approver and searches the face image database stored in the storage circuit using the analysis result. The approval circuit approves the document based on the search result. The editing circuit attaches one of an electronic stamp and an electronic signature to the approved document.