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The samples from several treatment units in wastewater treatment plant (WWTP) and different sample sites of receiving waters were characterized using excitation-emission matrix (EEM) fluorescence spectroscopy. After analyzed by parallel factor analysis (PARAFAC) method, the EEM fluorescence spectra of the principal components and fluorescence intensity scores matrix were acquired. Results showed that protein-like and fulvic-like substances were the main components of the samples from the WWTP and the receiving water body. The intensity of protein-like fluorescence in the influent samples was rather strong, and those of the following samples decreased significantly. The protein-like fluorescence intensity of the samples was relatively weak from the upstream of receiving water body, while those of the samples increased significantly from the water body near the urban area. The protein-like fluorescence intensity of upstream samples of the WWTP disposal outlet was stronger than that of downstream in the receiving waters. The fluorescence intensity scores of protein-like substance could be correlated with the COD concentration of the samples and the correlation curves were established. The correlation coefficient of the WWTP samples was 0. 930 and that of receiving water body samples was 0.913. The protein-like fluorescence could be used to evaluate the organic pollution of the samples. This study will provide a new method to investigate the operation status of WWTP and corresponding effect on the receiving water body.