Primarily this paper analyses the internal correlation between comparative advantage and competitive advantage, and holds that there are no conflict and contradiction between the two. the industries with comparative advantage often easily to have strong comparative advantage. Then this paper analyses the factors influencing regional agricultural competitiveness, including resources endowment, ecological environment, quality of labour forces, infrastructure, technology innovation and transformation capacity, industrialization degree, relevant support industries, market demand structure, government management and policy and so on. Finally, based on the analysis of conversion mechanism of regional agriculture from comparative advantage to competitive advantage, this paper puts forward the countermeasures for promoting regional agricultural competitiveness as follows: vigorously develop agricultural industrialization, and foster the leading enterprises; improve the national policy system for supporting agriculture, and increase the inputs into infrastructure and scientific research innovation; promote the development of related industries and support industries, and promote agricultural competitiveness; increase consumers' demand for the quality of agricultural products, and propel business investment and innovation.