In this work,the interaction between chelerythrine(CHE)and guanosine is studied using UV-vis and fluorescence measurements at various temperatures.The UV-vis spectra show that the increasing guanosine concentrations result in the decreasing absorption intensity and red shift of CHE E absorption band(267 nm).The fluorescence spectra are fitted to linear analysis,yielding a binding constant of 1.04×0~4 L/mol at 298.15 K of CHE with guanosine.Besides,with△_rH_m~θ=-8.26 kJ/mol,△_rG_m~θ=-22.90 kJ/mol, and△_rS_m~θ=49.38 J/(mol K)the interaction should be entropy-driven and exterothermic.