An analytical model for sensitized fluorescence has been developed. Some electron collisional transfer rates between excited states of the atom can be calculated from this model using experimental data of both sensitized and direct resonant fluorescence. As an example, the collisional transfer rate from 33D to 33D and the total de-excitation rate of 33P of neutral helium have been determined with this method in a partially ionized helium plasma in which the electron density and electron temperature are 5×10 14 cm-3 and 1.1 eV respectively.