The invention discloses an on-board automatic diagnosis integration system. The system adopts an OBD interface which includes an engine diagnosis CAN line, an engine calibration CAN line, a bus instrument diagnosis CAN line, an ABS diagnosis line, and a new energy DLC diagnosis CAN line. The OBD interface is provided with aperture positions thereon, and each aperture position has fixed definition, which can avoid redundant operations brought by different definitions. According to the invention, the system increases a plurality of diagnosis lines without increasing cost, and provides convenience for acquiring data from services such as new device tests, entire vehicle offline debugging, and after-sales service. When an entire vehicle instrument reports a breakdown, problems can be determined by reading internal data of the instrument or the entire vehicle CAN data through the OBD interface, which avoids tedious operations, such as dismounting the instrument.