An electronic file browsing system includes an electronic file delivery device and a file processing server. When document file browsing is requested from a mobile phone, a mobile phone access server in the file delivery device creates link information including session ID as authentication information and sends it to the mobile phone. Based on this link information, the mobile phone accesses the file processing server. The file processing server obtains session ID from the mobile phone and adds this session ID to the delivery request of the document file to the mobile phone access server.