The ambitious level of greenhouse gas emissions reduction in international shipping has been further enhanced by the MEPC 80 meeting， and the accounting requirements for greenhouse gas emissions based on the full life cycle of ship fuels have changed the “rules of the game”. All parties are actively promoting the process of shipping emissions reduction. There are differences in the development foundation and characteristics of the fleet， which leads to differences in the choice of emission reduction paths among different fleets. Taking a certain shipping company's ocean going fleet as the research object， a carbon reduction analysis model was established to analyze the conventional petrochemical fuel path， methanol fuel path， and ammonia/hydrogen fuel path. The carbon reduction emissions and carbon reduction costs of each path were explored， and short-term and long-term carbon reduction routes applicable to domestic fleets were proposed.