The invention relates to a method for detecting the inclination of a camera die set based on frequency spectrum analysis. The method comprises the following steps: generating a beam of coherent light and enabling the coherent light to be perpendicularly reflected to an objective lens in the camera die set; acquiring a diffraction spectrum image generated by reflection of a sensor chip; calculating the geometric center position of the diffraction spectrum image, and the central position of a zero-level frequency spectrum of the diffraction spectrum image; judging whether the camera die set is inclined or not by judging whether the central position of the zero-level frequency spectrum of the diffraction spectrum image is coincident with the geometric center position of the diffraction spectrum image. Through the adoption of the method disclosed by the invention, the accuracy of detecting the inclination of the camera die set can be improved.