This paper proposes a mathematical model and computation method for determining the attitude misalignment parameters of a geostationary meteorological satellite. The mathematical model is built based on the observation geometry. Mathematical modeling of the attitude misalignment parameters for landmark navigation and star navigation are both considered. The analytic solution for the model is also given. Theoretical analysis shows that there is no effective solution if there is only one observation. This paper has provided an important theoretical foundation for the image navigation system of a geostationary meteorological satellite.