A method for remote vehicle diagnostics, performed by a remote diagnostic system comprising a device connector, a vehicle connector, and a diagnostic device, the method comprising: receiving, by the device connector, a third data packet transmitted by the vehicle connector; converting, by the device connector, the third data packet into a user datagram protocol, UDP, data packet of the vehicle; broadcasting, by the device connector, the UDP data packet of the vehicle; activating, by the device connector, a transmission control protocol, TCP, server identical to a TCP server of the vehicle; receiving, by the diagnostic device, the UDP data packet of the vehicle, and creating, by the diagnostic device, a TCP client to connect with the TCP server of the device connector; notifying, by the device connector, the vehicle connector and creating, by the vehicle connector, a TCP client to connect with the TCP server of the vehicle; after the notifying: receiving, by the device connector, a TCP data packet of the diagnostic device in a TCP communication manner, encapsulating, by the device connector, the TCP data packet into a first data packet, and transmitting, by the device connector, the first data packet to the vehicle connector through remote communication; converting, by the vehicle connector, the first data packet received into a TCP diagnostics instruction data packet and transmitting, by the vehicle connector, the TCP diagnostics instruction data packet to a vehicle; receiving, by the vehicle connector, based on TCP communication, a TCP diagnostics response data packet returned by the vehicle according to the TCP diagnostics instruction data packet, encapsulating, by the vehicle connector, the TCP diagnostics response data packet into a second data packet, transmitting, by the vehicle connector, the second data packet to the device connector through the remote communication; converting, by the device connector, the second data packet received into the TCP diagnostics response data packet and transmitting, by the device connector, the TCP diagnostics response data packet to the diagnostic device; and obtaining, by the diagnostic device, a diagnostics result by analyzing and processing the TCP diagnostics response data packet and presenting, by the diagnostic device, the diagnostics result to a user. receiving, by the device connector, a third data packet transmitted by the vehicle connector; converting, by the device connector, the third data packet into a user datagram protocol, UDP, data packet of the vehicle; broadcasting, by the device connector, the UDP data packet of the vehicle; activating, by the device connector, a transmission control protocol, TCP, server identical to a TCP server of the vehicle; receiving, by the diagnostic device, the UDP data packet of the vehicle, and creating, by the diagnostic device, a TCP client to connect with the TCP server of the device connector; notifying, by the device connector, the vehicle connector and creating, by the vehicle connector, a TCP client to connect with the TCP server of the vehicle; after the notifying: receiving, by the device connector, a TCP data packet of the diagnostic device in a TCP communication manner, encapsulating, by the device connector, the TCP data packet into a first data packet, and transmitting, by the device connector, the first data packet to the vehicle connector through remote communication; converting, by the vehicle connector, the first data packet received into a TCP diagnostics instruction data packet and transmitting, by the vehicle connector, the TCP diagnostics instruction data packet to a vehicle; receiving, by the vehicle connector, based on TCP communication, a TCP diagnostics response data packet returned by the vehicle according to the TCP diagnostics instruction data packet, encapsulating, by the vehicle connector, the TCP diagnostics response data packet into a second data packet, transmitting, by the vehicle connector, the second data packet to the device connector through the remote communication; converting, by the device connector, the second data packet received into the TCP diagnostics response data packet and transmitting, by the device connector, the TCP diagnostics response data packet to the diagnostic device; and obtaining, by the diagnostic device, a diagnostics result by analyzing and processing the TCP diagnostics response data packet and presenting, by the diagnostic device, the diagnostics result to a user.