Abstract: There is trade-off effect between emissions of PM and No. To decrease one will lead to the increase of the other. Butanol blended combustion plus Miller cycle is one of the potential schemes to have both of them reduced. A simulation experiment is designed to find optimal parameters. The combustion chamber model of 4190 Z_LC marine diesel engine is constructed with AVL-FIRE and verified. Simulation experiments with variable combination of butanol blended combustion and Miller cycle arrangements are performed. The simulations indicate that for the compression ratio of 16.5, the blending ratio B30 and Miller degree M20 combination works best. It is demonstrated that under same indicated output, the specific fuel consumption reduces by 3.02%, the NO mass fraction decreases by 13.6% and the PM mass fraction decreases by 34.01%.