According to the precise quantitative requirements of clinical medicine field in CRP concentration of blood detection, a design of highprecision CRP fluorescent detector based on STM32F429IGT6 processor was introduced in this paper. Firstly, the working principle based on fluorescence immunechromatographic technology and the nonlinear regression quantitative model that can achieve accurate quantitative detection were presented. Secondly, the hardware and software design of detector is described in detail. Finally, many test that has been verified by commercial detector have been done to show that the quantitative error is less than 5% and the repetition error is less than 3%, in line with the detection requirements of clinical medicine.