2010年簽訂海峽兩岸經濟合作架構協議（ECFA）後，兩岸貿易障礙逐漸減少，商務往來日益增加，臺商大陸投資不動產時有所聞。兩岸的社經文化不同，工程合同制度有間，特別是大陸「黑白合同」問題相當突出，因為與臺灣的工程契約不盡相同，主要在於前者為二份合同，其效力判斷方式各有不同，後者僅一份契約，相較之下效力比較單純，容易判定，所以深為臺灣實務界所不解；雖然大陸司法解釋對黑白合同予以規範，但對黑白合同的法律效力為何？誠非臺商所能預期。除司法解釋未明確規範外，亦未釋明黑白合同的適用條件及效力，導致法律適用混亂。本文主張應從民法上認定黑白合同的法律效力，並依據《招標投標法》對「黑白合同」作區分，依據是否招標和備案分別認定，尤其是尊重當事人意思自治，限縮司法解釋的適用。至於如何判斷黑白合同的實質內容是否一致，則應依對工程品質、合同價款及工程期限的影響，以及合同是否備案而判斷。

Since the signed ECFA in 2010, the barriers of trade is gradually reduced on Cross-strait trade, then business is obviously increasing especially real estate investment from time to time. Based on the difference of social, economic and culture, the legal system of construction contract is not the same. Especially mainland China, ”lack and white construction contract” problem is quite prominent, because of the differ in construction regulation with Taiwan, mainly in the former two documents of the contract valid way to judge different opinion, the latter is only a contract documents, the legal effect of contrast is simple for judgment in comparison, easy to determine. Nowadays, the black-and-white construction contract is the common phenomenon of the mainland's construction market that is significantly puzzled by the judicial practice on Taiwan. Although the judicial interpretation of Mainland to be black-and-white construction contract specification, but what is the legal effect of the black-and-white contract? That cannot be expected by Taiwan businessmen. In addition to judicial interpretation is not clearly defined, nor decide the legal effect and application of black-and-white construction contract, however, that will derive to disputes in the application of law. This paper argues that decide the legal effect of black-and-white construction contract from Civil law and distinguish between types difference by the Bidding law, respectively, depending on whether the tender, bidding and register for the contract. Furthermore, it is important to respect for Party Autonomy principle of contract and make the judicial interpretation clear for application. How to determine whether the substances content of black contract and white construction contract are consistent, that should be judged according to the engineering quality, the contract price and the impact of the project deadline and whether the contract for registered.