Fluorescence and electrofluorescence spectra of perylene molecules doped in a polymer film at different concentrations have been measured at different temperatures in the range of 70-295 K. At high concentrations where excimer is formed, LE fluorescence emitted from the locally excited state of perylene is quenched by an electric field at any temperature, indicating a field-induced enhancement of the excimer formation rate. Fluorescence of the Y-type excimer of perylene molecules shows a field-induced enhancement at room temperature, whereas it shows a field-induced quenching at low temperatures. The temperature dependence of the electric field effects on fluorescence has been discussed. (c) 2006 Elsevier B.V. All rights reserved.