Embodiments of the present invention relate to the field of diagnostic technologies of a vehicle, and specifically disclose a diagnostic method for a vehicle. The method includes: receiving, by a diagnostic server, a connection request message sent by a terminal, the connection request message being used to request address information of a diagnostic server corresponding to a to-be-diagnosed vehicle; determining the corresponding diagnostic server according to the connection request message; and sending the address information of the diagnostic server to the terminal, so that the terminal establishes a communication connection with the diagnostic server according to the address information. According to the foregoing technical solutions, in the embodiments of the present invention, a plurality of vehicle can be diagnosed by using the terminal, improving diagnostic efficiency and achieving relatively high user experience.