Abstract: This paper focused on green chemistry, and carbon quantum dots were synthesized using soybean protein as raw material and one-step hydrothermal method. The results of Fourier infrared spectroscopy showed that there were hydrophilic groups such as carboxyl and hydroxyl groups on the surface of carbon points. The optimal excitation wavelength was determined to be 370 nm by fluorescence spectroscopy and the optimal emission occured at 443 nm. At the same time, orthogonal test was used to analyze the effects of different experimental conditions on the yield of carbon quantum dots. The yield of fluorescent carbon quantum dots of soybean protein was the best when the hydrothermal reaction time was 3 h, the hydrothermal reaction temperature was 180 ℃ and the mass of citric acid was 2 g. The synthesized carbon quantum dots had good water dispersibility and low biotoxicity.