In this paper, the methodology of real-time pesticide proportioning by spectral analysis technology is proposed for the first time. Used 0.5% Matrine as the research object. The spectral analyzer, flow cuvette, and peristaltic pump, etc., were combined used to create a real-time proportioning model. Specifically, the spectral data, which corresponding to different concentrations of Matrine under the transmission of the same light source, were measured. And then, its effective information was extracted for analysis. Finally, the least squares method was used to create the proportioning model. Through the experimental study, it can be demonstrated that the significant correlation between Matrine concentration and light intensity, with a linear R² of 0.93632, which correspond to the spectrum peak and Matrine concentration range from 659 nm, and 1.2 to 3.2ml/kg, respectively. In this paper, the viability of applying spectrum analysis technology to achieve pesticide formulation was proved. The system structure is simple, and effectively avoid the eliminating sophisticated control algorithms and system modeling, which can serve as a theoretical framework for accurate pesticide formulation.