The promulgation of the Contract Law of P.R.C. dose not quiet down the argument about the value location and the drafting model of the Contract Law of P.R.C. in the law field, and actually, it makes that argument more intense and acute. On the view of economic analysis, this article probes into the economic significance of contract law, especially its functions in saving the transaction costs of litigants, sharing the risk of contracts and so on. Furthermore, this article proposes the view about the economics explanation of incomplete contracts and how to disign the most efficient contract norms.