Although the duty to disclose information can play an important role in settling disputes arise from modern contract, it has not been adopted by Contract Law of China as a pre-contract duty which main obstacles are created by the presumption of parties to contract and the hypothesis of contract model of classical contract theory. However, challenged by modern transaction circumstances and new contract theories, the classical contract theory has been losing its legitimacy. Against this background, analyzing the said obstacles in detail and finding the rationality and value of the duty to disclose information in relational contract theory based on the characteristics of modern contract can help a lot in constructing the legal institutions of the duty in China.