As the deepening and the development of the Opening-up and Reform and the rising of the market economy,insurance plays a more and more important role in society.In such time,maritime insurance contract is in constant usage following the boom of ocean transportation.However,maritime insurance contract is seperated from common insurance contract because of its particularity,but it still applies to the principles for common insurance contract.Principle of honesty and credibility,also called the lifeline of insurance,is an important principle in Civil and Commercial Law,which is also the fundamental principle of Law of Insurance,but there is no specific rules about the principle in the Maritime Code of the Peoples Republic of China.According to the current condition of Chinas maritime insurance industry,honesty and credibility still need to be improved and if not improved,there will be negative effect on the continuous development of the industry.This essay will write about the principle of utmost good faith in maritime insurance contract and the comparison on the principle of utmost good faith between Law of Insurance and the Maritime Code.