A new spaceborne imaging method based on squint isometric scanning was presented to overcome the problems of resolution degradation and atmospheric radiation difference with scanning angle in traditional cross-track scanning imaging method. Firstly, the principle of this imaging method was introduced, and the geometric imaging model was established according to the theory of geometric optics. Then, based on the geometric imaging model, the relationship between the scanning direction spatial resolution, vertical scanning direction spatial resolution and width with the scanning angle were given. Furthermore, the expressions of resolution and width for multi-angle observation via satellite pitch were derived. Finally, the simulation results of one pre-research spaceborne imager show that the resolution degradation is greatly reduced. When scanning angle is 60°, the edge view resolution is 2.5 times of central field of view far lower than traditional cross-track scanning imaging method 9.5 times. It provides a new solution for wide width imaging and has a certain reference significance for promoting the development of super wide width, high resolution and multi-angle spaceborne remote sensing.