In order to expand the scope of application of shellac wax, nano-shellac-wax emulsions was prepared by Shah method through single factor experiment to choose factors and levels. Average particle size of the emulsion were optimized through response surface method with three factors and three levels based on principle of Box-behnken design. Results showed that the optimum average particle, the rate of mixing emulsifying temperature are 30.5nm, 15.9%, 890r/min, 90℃, respectively. The particle size, distribution and stability of shellac-wax emulsions are studied with the laser granularity analyzer.The average particle size of shellac-wax emulsions are below 50nm and were well-distributed.