The water from Tai Lake was analyzed by spectrum measurement and synchronous sampling with field portable spectroradiometer. The characteristic wave peaks of cyanobacteria and suspended particle were obtained from the spectra, and the corresponding relations between the heights of wave peaks and the concentrations of chlorophyll a and suspended particle were built. As a result, a quantitative retrieval algorithm is deduced, and the algorithm is applied in the image acquired by OMIS imaging spectroradiometer.