Spectral image information provided by multispectral remote sensing cameras has extremely high application value. In order to break through the limitation of the number of spectral segments of CCD imaging devices and increase the number of spectral segments of a single camera, a two-channel solution was proposed. Starting from the optical system, a high-stability opto-mechanical structure was designed for a dual-channel off-axis multi-spectral remote sensing camera. Firstly, the high stability support of the large-diameter primary mirror was realized by using the four-point spherical support technology, which ensured that the mirror surface shape accuracy met the use requirements under various working conditions. Then, the camera′s focal plane component, main frame and vibration isolation system were designed and optimized to ensure that the dual-channel off-axis remote sensing camera had good structural stability while providing eight multi-spectral segments. Finally, the finite element analysis andmechanical environment test of the entire camera show that the camera has high stability and meets the design expectations.