Regional policy of the European Union (EU) opens numerous opportunities for its Member States, regions and cities with the aim to improve their economic growth, but also quality of life. The aim of this final thesis is to analyse the changes of the Irish economy, before and after the EU accession, with emphasis on the implementation of the regional policy, due to the fact that Ireland has achieved accelerated economic development and represents interesting, successful example for the other Member States. After the description of the main characteristics of the EU regional policy development, this work describes that the development of the Irish economy was the result of the common influence of the internal and external determinants, market opening, investments attraction, and strengthening the basis for reform performing such as is its education system. Comparison of different indicators before and after the EU accession has proven that it is possible to extract the benefits for entering the integration. EU funds absorption has resulted with positive effects which are presented in this thesis in more detail according to chosen areas (such as entrepreneurship, research and development, education and labour market, infrastructure etc.).