The ocean color and temperature remote sensor is an important tool for monitoring the marine ecological environment, assessing primary productivity of the ocean, and studying global sea surface temperature changes. New generation ocean color and temperature scanner addresses the shortcomings of traditional ocean color remote sensors in terms of spatial resolution, spectral range setting, signal-to-noise ratio, and calibration accuracy. For the first time in China, a system design scheme for telescope overall rotation scanning and half angle mirror synchronous tracking is proposed. Firstly, an innovative rotating off-axis three mirror optical system was designed, combined with scanning imaging mode and a large pixel detector design, achieving system sweep width ≥3000 km, signal-to-noise ratio ≥1000, noise equivalent temperature difference of infrared band ≤0.1 K, system polarization sensitivity ≤1.5%, and stray light coefficient ≤1%. Secondly, in response to the demand for multi band and high-precision calibration on board, a full aperture and full path onboard calibration technology based on a rotating telescope has been proposed, which improves the solar calibration accuracy of the payload to within 2%. The performance test results indicate that the system surpasses comparable load-bearing systems both domestically and internationally in multiple metrics, the research results can provide technical support for the new generation of ocean color and temperature scanner in China.