ABSTRACT At this new era of the 21st century, the EU stands out as an important regional organisation. It has expressed its desire and ambition to take up a prominent place in international relations, and the development aid policy is an important tool to serve this mission. Nowadays the development aid policy has become a crucial instrument of the EU external action: internally, it is an important indicator of the width and depth of the EU integration; externally, it is an instrument for the EU to enhance its impact on the international affairs and to promote the EU values to the rest of the world. This thesis firstly gives an overview of the EU development aid policy. Several relative concepts are introduced so "development aid" can be defined more precisely. Besides, the thesis introduces the working process of the European Commission on development aid and the fund of the EU development aid policy. The thesis also recognizes that the EU development aid policy has been existed for more than half a century and taken great evolution both in its scope and depth. Then this thesis goes through the legal basis of the EU development aid policy. The basic treaties, the regulations, the soft law within the EU, the UN Charter and other international agreements the EU has joined are all reviewed. Since the policy was born in the year 1957, the basic treaties have changed a lot, and also the EU has contributed a lot to the development policy in international level under the framework of UN. This thesis further examines specific case concerning the situation of the EU development aid conceived in the ACP countries. The EU development aid policy in the ACPs is implemented under series of agreements, such as Yaoundé Convention I and II, Lomé Convention (Lomé I to Lomé IV) and the Cotonou Agreement. It is also worth to note that in recent years, the participation of the prospering civil society is a most important promotion in the EU-ACP cooperation. The policy has shown the huge challenge both the EU and its Member States face up to: the effectiveness of the development aid. Irrespective of its big size in quantity, the implementation of the EU development aid programmes is not in a satisfactory condition. The author proposes tentative solutions according to the negative factors affecting the quality of aid: adoption of a unified EU budget on development aid policy; new Member States' adaption to the role of donor; a call for the EU and Member States coordination; implementation of country ownership principle; a balance of the EU interest and conditionality; avoiding the interruption of trade on aid. However, the problem of the EU development aid effectiveness can never overweight its advantages compared with the U.S. foreign aid. The EU development aid is much bigger in quantity (including the European Commission and the Member States aid), and there is much less direct pursuit of state's interest, and much more public support on the EU development aid than the U.S. foreign aid. Finally, the thesis investigates the EU development aid in China. As the largest developing country all over the world, China has always being the major concern of the EU development aid. Began in 1980s, the EU development aid in China is the most remarkable contributor to the EU-China relations, both as a balance of the existed irritants in bilateral relations and as an instrument of enhancing the mutual understandings. This thesis also examines the EU and Member States aid in China respectively, specifically two powers of Europe: Germany and France. Chinese government welcomes the EU development aid through the equitable cooperation, with the basis of the common interests and a mutual respect of the basic institution and governance, especially a respect of the state sovereignty. Although with plenty of challenges and global economic recession ahead, the EU should recognise that giving a hand to poorer countries at this critical point will benefit everyone. Not only should the EU maintain its development activities, but it should also transform them into an engine for growth.