The invention discloses a mobile fitting diagnosis on-board platform based on Internet. The mobile fitting diagnosis on-board platform comprises a vehicle, the compartment of which is divided into a hearing audiometry chamber, a display fitting studio, and an ear mold producing chamber by acoustic barrier boards; an on-board terminal, which comprises a data, query, and communication unit, and a vehicle management unit; a client, which comprises a data acquisition unit, a query unit, a reservation unit, and a prompting unit. The client and the on-board terminal are respectively connected with an Internet server data management terminal by the Internet, and the Internet server data management terminal comprises a storage platform, a processing platform, an analysis platform, an on-line expert support platform, and a vehicle positioning and management platform. The mobile fitting diagnosis on-board platform has advantages of large fitting resource coverage, high resource utilization efficiency, and abilities of relieving hearing aid consultant resource shortage, improving profession levels of hearing aid consultants and physicians, helping hearing impairment patients in remote areas, and providing accurate data support for care strategy made by government for hearing impairment patients.