A virtual paper reading device comprises a virtual paper reading device for viewing a document from a screen through a mobile device; wherein the document to be read has a size as an original size and an original printed page; a 3 axial sensor in the mobile device for sensing moving direction of the mobile device; a key set for adjusting a size of the document to be presented and a present area of the document to be presented; and an application software for receiving the moving direction message from the 3 axial sensor and adjusting signals from the key set so as to adjust a present area and a size of the document to be presented on the screen of the mobile device. The user can read the message from the document easily and conveniently.