Phycoerythrin (PE) is an important indicator which measures the algae eutrophication in water. Visible absorption spectrometry has some advantages, such as rapid detection, accurate, no secondary pollution, on-line and in-situ measurements etc. Therefore, the method of detection phycoerythrin contents by visible absorption spectrometry is proposed. Based on the standard solution of phycoerythrin as experimental subjects, the visible absorption spectrometry of the standard solution are collected in the range of 5 ~ 250 mg/L, and the correction analysis model is made. The spectral preprocessing is performed in different spectral region and the Partial Least Squares (PLS) algorithm is used to establish the correction analysis model. Compared with Principal Component Regression (PCR) algorithm, the results show that the correction analysis model has the highest correlation and smallest error by the PLS algorithm made in the spectral region of 480~570 nm. The correlation coefficient root mean square error of calibration and relative standard deviation is 0.9930, 5.5783 and 3.92%, respectively.