Novel, fluorescence active cellulosic polymers with high degree of functionalization of up to 1.0 were synthesized in homogeneous phase (cellulose in N,N-dimethylacetamide/LiCl and 6-O-thexyldimethylsilylcellulose in pyridine) with a mixed anthracene-9-carboxylic/p-toluenesulfonic acid anhydride. This novel and effective synthetic method yield the pure carboxylic acid esters of the polymers, which were characterized by means of FTIR-as well as H-1 and C-13 NMR-spectroscopy. The polymers show typical fluorescence spectra, which are identical with the non-bond anthracene-9-carboxylic acid.