The invention provides a TOF-PET image reconstruction method based on the compressed sensing theory. The method includes the steps that firstly, according to the flight time positioning imaging principle, a first image is reconstructed based on a data set obtained through a TOF-PET detector and an initial image through a TOF reconstruction algorithm; secondly, according to the compressed sensing theory, a sparse representation of the first image is solved with lp norm minimality as the purpose, the first image is updated according to the solution result, and then a second image is obtained; thirdly, whether a stop condition is met or not is judged, if yes, the second image is a final image, if not, the initial image is updated to be the second image, and the first step is executed again. By means of the TOF-PET image reconstruction method, given time information can be completely utilized, acquisition time is shortened, and the drug dose is reduced; meanwhile, the image signal to noise ratio can be increased, noise can be remarkably suppressed, and therefore better image quality can be acquired.