The present specification provides a two-dimensional code identification method and device, and a two-dimensional code positioning and identification model establishment method and device. The two-dimensional code identification method includes: obtaining a to-be-identified two-dimensional code, and performing global feature positioning detection on the to-be-identified two-dimensional code by using a pre-established two-dimensional code positioning and identification model; performing focus adjustment, based on a predetermined image resolution, on the to-be-identified two-dimensional code on which positioning detection is performed; and decoding the to-be-identified two-dimensional code on which focus adjustment is performed. The present specification can improve the identification accuracy of two-dimensional codes shot in complex scenarios.