Abstract: A self-adaptive multi-scale respiratory monitoring method based on a camera, relates to the technical field of video image signal identification processing, in order to solve the defect that the local optimal respiratory signal and the global optimal respiratory signal cannot be acquired by single image scale, a method was provided: (1) acquiring a respiratory monitoring object in real time;(2) performing multi-scale regular pre-segmentation on a video image, performing local respiratory signal identification and extraction on each unit area pre-segmented under each scale respectively, and defining the unit area with local respiratory signal output as a target area; and (3) comparing local respiratory signals extracted from the target area pre-segmented under each scale, determining an optimal segmentation scale, and taking a local respiratory signal extracted from the target area under the optimal segmentation scale as a monitoring respiratory signal output.