The invention provides a retrieval method and a retrieval device of
chlorophyll a concentration of inland case II water, wherein the retrieval method of the
chlorophyll a concentration of the inland case II water comprises the steps of firstly, classifying first
remote sensing reflectance spectra to obtain a plurality of second
remote sensing reflectance spectra taking different components as main components; calculating the weight matrixes of all the second
remote sensing reflectance spectra, selecting all characteristic wave bands and calculating the
chlorophyll spectral indexes; finally, carrying out weight fusion on the chlorophyll spectral indexes under all categories of all the spectra by weight to obtain weighted chlorophyll index, and fitting an inversion model to obtain the
chlorophyll a concentration. Due to the method of firstly classifying and then carrying out weighted inversion, the limitation on the retrieval method caused by the area and the time can be reduced, and the smoothness and the stability of inversion results can be improved, and therefore, when the
chlorophyll a concentration of a certain second
remote sensing reflectance spectrum is inversed subsequently, the
chlorophyll a concentration can be obtained by inversion through the inversion model corresponding to the second
remote sensing reflectance spectrum, so that the universality of the method is improved.