Clinical chemistry analyzer based on reflectance spectroscopy is widely used in medical institutions. This article presents a novel design of calibration method for the essential metrological parameters of the analyzer, such as “relative indication error”, “repeatability”, and “linear correlation coefficient”, by studying the working principle of the device. The experimental verification results and uncertainty analysis show that the calibration method presented in this article can establish the metrological traceability system of clinical chemistry analyzer based on reflectance spectroscopy in China in order to ensure the accuracy and reliability of the device, which is of great importance for the quality control of the device.