The invention discloses a DSP-based assembly line autotest method of a protection and monitoring device. The method specifically comprises the following steps that (1) one or more test items are selected by debugging personnel through a menu, and each test item comprises an alternating current sampling board test, a communication board test, an input and output board test, an operation panel test and a human-machine interface test; (2) as for the selected test items, test boards corresponding to the selected test items are connected with the protection and monitoring device to be tested; (3) after the tests of the selected test items are finished, test results of the protection and monitoring device are output through a human-machine interface, wherein if it is prompted that the tests are passed, it is indicated that the protection and monitoring device is up to standards and can be put in storage, if it is prompted that the tests are abnormal, troubleshooting is conducted on the protection and monitoring device. According to the DSP-based assembly line autotest method of the protection and monitoring device, a complete-machine test or a single-board test can be selected according to requirements, the test mode is flexible, a test of qualification or disqualification is judged through software, the interference caused by human factors is reduced, and the debugging efficiency and the quality of the protection and monitoring device are improved.