This work reports the use of the steady state fluorescence (SSF) technique to study dissolution of a composite film formed from a mixture of Al2O3 and polystyrene (PS) latex particles. The composite films were cast from dispersion of pyrene (P)-labeled PS particles in Al2O3 solution at room temperature and annealed at 280 C temperature for 10 min. Eight different composite films were studied in various latex contents. Toluene was used as dissolution agent. Fluorescence intensities I-P from P were monitored during dissolution. Fickian diffusion was employed to model the dissolution processes. Dissolution coefficients, D-d, were measured and found to be increased at high PS content in the composite films.