東協於2002年建構自由貿易區乃積極促進區域投資之發展，以尋求在各種投資之便利化與自由化措施機制，以法制規範輔助貿易投資規模的具體實踐。東協得以順利實現自由貿易區，其形成因素中比較被研究者所忽略者即是「法制因素」，此為本文探討的課題，本文將東協各項投資法制的內容與原則作系統性的歸納分析。本文研究認為：經貿投資合作發展催生了法制，而法制的完備保障東協經貿投資之有效運作。無完備的法制經貿投資合作就無以為繼，然而，東協投資合作的法制歷程，仍然面臨諸多困境有待解決。2008年東協憲章揭示東協一體化若干理想目標與投資爭端解決規則，但對於設立屬於東協區域法院卻仍無規範，其他如東協成員國複雜共識仍需要時間、對經貿協商原則的羈絆、傳統東協模式面臨的障礙與調整等，均為經貿投資法制所面臨的局限性。

Since its establishment in 2002, ASEAN Free Trade Area has actively promoted the development of regional investment. Among all factors to success of ASEAN Free Trade Area, the most apparent one ignored by researchers is "legal factor". In this context, a systematically summarized analysis was made on the content and principles of a variety of laws and regulations relevant with investment. Though the ASEAN Charter in 2008 revealed rules of solving dispute raised by the ASEAN integration, the obstacles of the principles of economic and trade consultation, the adjustments on difficulties faced by the traditional ASEAN still need to be solved.