Global warming has been drawing researchers’ attention for decades and in marine industry many different strategy and technologies are introduced to mitigate the global warming effect. As a main contributor to global warming, carbon dioxide has been targeted as a significant emission to reduce from marine activities and there are many carbon emission reduction technologies introduced to shipping. However, the results of the reduction are varied and an evaluation tool to investigate their performances in a long term are necessary. Life cycle assessment is an evaluation method considering a product or system’s life span, from cradle to grave, covering all the activities which generate carbon emissions. While applying new carbon reduction technologies, the emissions from different activities are estimated and determined through life cycle assessment. Considering the related costs, a life cycle economic assessment can illustrate the overall savings with the application of carbon emission reduction technologies. Currently the assessments have been conducted to evaluate the applying of hybrid propulsion system, selection of engine configuration, utilization of solar panel array, adoption of carbon capture system, determination of maintenance strategy and so on. The results have indicated the performances of these carbon reduction methods from the perspectives of environment and economy which indicates that life cycle assessment is a feasible and comprehensive evaluation tool for the performance evaluations on carbon reduction techniques.