Abstract: Quantitative analysis the content of original orange juice by using synchronous fluorescence spectrometry. Preprocess the synchronous fluorescence data of the samples and establish the original fruit juice content prediction model by selecting different spectral bands with partial least square(PLS) method,then predicte the validation set samples to verify the accuracy of the model and the feasibility of the method which was selecting different spectral bands with partial least square( PLS) method. The results showed that the spectroscopic data by smoothing with first derivative treatment was more suitable for establishing model,the performance of the model which was established by the spectral band was better than that established by the range of wavelengths. The prediction of the root-mean-square error which was predicted by the final optimal model was 0.035832,the coefficient of determination(R2) was 0.972570. Thus illustrates synchronous fluorescence spectrometry combining with PLS could realize quantitative analysis of the original juice content.