For risk management, ‘warranty’ provisions in common law serve to define the risk insured, whereas civil law countries adopt an ‘alteration of risk’ doctrine. The term ‘warranty’ under Chinese marine insurance law is derived from English law, whereas in its general insurance law China at the same time also adopts an ‘alteration of risk’ doctrine to control risk. The need for a reform of insurance warranty law has prompted much scholarly debate. Following a thorough discussion of the status quo of warranty law in China, this paper further explores the reformed warranty law under the Insurance Act 2015 in England, together with the general ‘alteration of risk’ doctrine in civil law countries. It is argued that blindly importing relevant articles from the Insurance Act 2015 is not a feasible solution, as this will not only create more disputes, but will also create inconsistency with other laws. The paper concludes by suggesting that maybe adopting the ‘alteration of risk’ doctrine is a better way to replace the current warranty law under Chinese marine insurance law.