Due to its complex spatial distribution, the higher-order Hermite-Gaussian modes has a wide range of applications in precision measurement, optical communications, and laser processing. Although the higher-order Hermite-Gaussian modes can be efficiently generated using cascaded spatial light modulators, the experimental system has extremely high alignment requirements for the optical field and the hologram, which becomes a key factor limiting their high-quality generation. This paper provides a deep analysis of the impact of misalignment between the optical field on the plane of the second spatial light modulator and the hologram loaded onto it. The results indicate that microlevel alignment in the lateral direction and millimeterlevel alignment in the longitudinal direction are required between the optical field on the plane of the second spatial light modulator and the hologram loaded onto it. Additionally, this paper proposes an experimentally simple method to achieve precise alignment between the optical field on the plane of the second spatial light modulator and the hologram loaded onto it, providing important reference for efficiently generating the higher-order Hermite-Gaussian modes with high quality. This research is of great significance for advancing the development of optical imaging, precision measurement, quantum information processing, and other fields.