A vibration detecting apparatus (100), comprising a light source assembly (11), a diffractive optical element (12), an image acquisition device (13), and an image processing device (14). The light source assembly (11) is at least partially attached to an object (900) to be detected. The diffractive optical element (12) is used to diffract light emitted by the light source assembly (11), so as to form, on a photosensitive surface of the image acquisition device (13), a diffraction pattern that changes with the vibration of the object (900) to be detected. The image acquisition device (13) is used to perform image acquisition on the diffraction pattern. A plurality of reference patterns are stored in the image processing device (14), each reference pattern being associated with at least one reference amplitude. The image processing device (14) matches the diffraction pattern acquired by the image acquisition device (13) with the plurality of reference patterns, and takes the reference amplitude corresponding to the matched reference pattern as the actual amplitude of the object (900) to be detected. The vibration detecting apparatus (100) can quickly detect a vibration, and has high detection accuracy. Further disclosed are a vibration detecting method, a pulse diagnosis device (200) and a computer storage medium.