Abstract: The annual costs to a fleet are modeled under the condition of emission reduction measures introduced. The minimum costs with different emission reduction measures for optimized speed are calculated according to the scale of fleet. The measures with cost advantages are recommended. Liners running on four routes are investigated and the analysis shows that for current price of fuel oil, installation of the desulfurization tower is more acceptable in terms economy. The sensitivity of the costs of emission reduction measures to fuel oil price is analyzed. The analysis indicates that the cost of fuel conversion will go low as the price difference between alternative fuels and traditional fuels decreases. For the 4 liners, fuel conversion will become the best choice when the cost for doing it decreases by 40%. When LNG becomes 78% of high sulfur crude oil in price, converting to LNG will be a better choice than installing desulfurization tower.