The energy transfer between Aoridine Orange and Ppronine G.S. in the aqueous solution of sodium laurpl sulfate(SLS)was studied. It was found that, in the solution without SLS, the energy transfer cannot occur between dyes due to their low concentration. When SLS wag added, strong energy transfer was observed, even when the concentration of SLS was far less than the critical mioellar concentration (cmo) of the surfactant. These results indicated that before micelle formation a type of unstable premioallar structure which promoted energy transfer was probably present in the solution.