CMC/Eu(Ⅲ),CMC/Tb(Ⅲ),HPCMC/Eu(Ⅲ),HPCMC/Tb(Ⅲ) nanocomplexes were prepared,and the “antenna effect”,fluorescence properties,static and dynamic rheological properties and thermal properties of the products were investigated by means of XPS,UV-Vis,rheological detection and TG-DSC.XPS results show that Ln(Ⅲ)—O is formed in all the products of Eu³⁺ and Tb³⁺ reacting with CMC and HPCMC,and the UV ab- sorption of the products overlaps its excitation spectrum,which proves that the energy absorbed by cellulose deriva- tives can be successfully transferred to a rare earth metal to make it light.The results of the rheological properties of the nanocomplexes show that the solutions of all nanocomplexes are pseudo-complex,and the flow activation energy of the four kinds of nanocomplexes are 1. 5964,2. 5193,1. 6047 and 1. 4218kJ/mol respectively,suggesting that the viscosity is dependent on temperature.In addition,the storage modulus and loss modulus of the solution grow up with an increase of the angular frequency; the thermal properties of the nanocomplexes are similar to those of CMC-Na and HPCMC-Na,and the side chains on HPCMC are more readily associated with water through hydrogen bonding.