Marine digital seismic streamer BIT built-in test method, test system and terminal

The invention belongs to the technical field of marine streamer data processing, and discloses a marine digital seismic streamer BIT built-in test method, a test system and terminal, which are used for carrying out self-inspection and detection on system cavity temperature, system cavity humidity and system power supply state information of an OCC interface control box body, a cross station box body, a data transmission packet box body and a digital hydrophone. Real-time test is carried out on data transmission of each node, error checking is carried out on each node, and if the phenomena of code loss and code error occur, an error component is positioned; and the obtained positioning error component information is sent to an overwater control center, and closed-loop test and fault diagnosis display of digital seismic streamer BIT machine pre-work self-test, checking in work and checking after work are carried out. Closed-loop tests of self-inspection before work, check during work andcheck after work can be