To meet the user requirements for high resolution, high signal-to-noise ratio, wide dynamic range, and high revisit frequency in coastal zone observation, the coastal zone imager on the next-generation ocean color observation satellite employs an off-axis three-mirror main optical system and multi-spectral integrated high-sensitivity TDICCD detectors. This setup achieves high signal-to-noise ratio and wide dynamic range imaging across nine spectral bands under low water body radiance conditions, with a panchromatic spectral resolution of 5 meters and a multi-spectral resolution of 20 meters. The design of a large aperture pointing swing mirror, in combination with long-life mechanism design and high-precision closed-loop control, ensures the realization of high precision and reliability and the flexibility and maneuverability in orbit for the imager. The swath width, without the satellite side-to-side motion, reaches 1029 kilometers. Through ground testing and in-orbit operation verification, all performance indicators of the imager meet the design requirements and user needs. It has significant application prospects in enhancing coastal zone remote sensing observation capabilities, serving marine resource development and environmental protection.