Abstract: In order to establish indirect interaction patterns based on trust,three kinds of basic indirect interaction patterns are designed based on basic interaction patterns.The first kind always depends on middleman and the second kind depends on middleman during one-way authentication and the third kind depends on middleman during mutual authentication.Furthermore,the latter two kinds of basic indirect interaction patterns are modeled by improved inhibitor arc Petri nets and the method of evaluating degree of the trust is discussed.Finall,the use of bacis indirect interaction patterns in instablishing complex network indirect interaction patterns is illustrated by an example of C2C electronic business model.Compared with the general interaction pattern design,the designed indirect interaction patterns focus on how to instablish trustworthy and indirect interaction patterns based on trust relationships with middlemen when there is not enough direct trust.