The invention relates to the technical field of computer vision, and particularly discloses a fatigue driving early-warning method based on expression recognition. The method comprises the following steps of S1, obtaining images; S2, conducting face recognition and division; S3, conducting expression recognition; S4, pre-outputting a recognition result, wherein according to the expression recognition result at the last step, the preliminary recognition result is output; S5, judging whether the result meets the requirement or not, and if not, executing S1-S4 again; if yes, executing S6; S6, outputting the recognition result. By means of the fatigue driving early-warning method, big data is utilized for training a fatigue expression recognition network model, driver facial expressions whichare collected in real time are input to the model, a face image area is recognized and divided, expression analysis is conducted, and finally, whether a driver is in a fatigue driving state or not isjudged. The defect in the prior art that detection of fatigue driving of the driver is inaccurate is effectively overcome, the precision of detecting fatigue driving of the driver is improved, and thus the purpose of effectively reminding prevention of fatigue driving of the driver is achieved.