Intellectual property contract has relational contract attribute. Opportunism behaviors, especially the implicit ones, produce serious obstructing effect on effective performance of a contract, lead to unidirectional flow of intellectual wealth and cause the negative impact on the rise of transaction cost and social wealth consumption and so on. The input in the specific assets of transaction is an important factor to trigger opportunism behaviors, as a result, the opportunism behaviors in the period of the signing, modifying and performing of intellectual property contracts need to be prevented to boost the effective implementation of intelligent achievements.