Abstract: The suretyship is a form of guaranty,in which the performance of a contract(principal obligation) is guaranteed by entering into a suretyship contract on the surety’s general property.The suretyship is independent in some way,which is neglected to some extent by our theory and legislation which mainly focuses on its dependence on the principal contract.In this paper,the authors analyze the independence of the suretyship from such aspects as the development of the suretyship,its conclusion and content,the scope of the suretyship guaranty,causes leading to the alteration or effect of the suretyship,the surety’s right of defense,etc.and point out the theoretical and practical significance of stressing the independence of the suretyship.