Information sharing system, on-vehicle diagnosis terminal, and display terminal

An information sharing system (1) including a plurality of on-vehicle diagnosis terminals (10) and one or a plurality of display terminals (20) and sharing diagnostic information over wireless communication. The terminals (10, 20) include a first determination unit S7, S8 and a second determination unit S34, S35 configured to determine whether or not predetermined times T1, T2 have passed from stored clock times C1, C2 at which data sets DS are acquired from the any of the other terminals (10, 20). When the predetermined times have passed, new data sets DS are acquired and the storing into an other-vehicle data storing unit 15B and a data storing unit 25A is performed. When the predetermined times have not passed, new wireless communication is established with communication units (13, 23) of the terminals (10, 20) capable of establishing wireless communication.