An invention is optimizing method using for large marine crankshaft sleeve heater emulate project. It sets up an emulate model of the crankshaft sleeve heater. It starts to emulate the computer three dimension numerical values of the crankshaft sleeve hole heater process, under the boundary condition, after given all kinds of boundary conditions of the emulate model. And it gets the parameters of sleeve hole and the crankshaft of many heaters emulates projects during the heating process. Then examines the experiment determine and emulate result of the heat physical parameters in the heater emulate projects and optimizes the crankshaft sleeve heater emulate model; thus compares the parameters in order to confirm the best sleeve heater emulate model. It uses computer digital analysis and simulation instrument, so the project confirmed by this method can be used in the large marine crankshaft sleeve machining process. And the crank temperature of the crankshaft work piece ascends steadily and the heating is much more homogenizes with the temperature different inside 10 degrees. The sleeve hole of the crankshaft work piece equably enlarges strictly in circle shape, in order to accord with the technical demand of the crankshaft sleeve.