A flange-mounted connector capable of achieving thread self-locking comprises a flange socket, a tooth sleeve, a gear sleeve, a driving spring and a plug. The flange socket and the tooth sleeve are fixed to a flange plate together, the gear sleeve and the driving spring are installed on the plug, the gear sleeve is meshed with the tooth sleeve under the effect of the driving spring after the plugand the socket are combined in a thread screwing mode, therefore, thread self-locking is achieved, and thread loosening is prevented.