This paper aims to assess the correlation between economic competitiveness and innovation potential within the European Union in the context of Brexit. For the quantitative evaluation of the mentioned relationship, we use the World Economic Forum Index as a proxy variable for economic competitiveness, respectively the following five indicators for different dimensions of the innovative potential at the level of EU member states: gross expenditures on R&D, R&D personnel, innovative enterprises, patent applications, and high-tech exports. In our research, we want to find out the impact of Brexit on the correlation between innovation and competitiveness in the EU, in which sense we demonstrate the hypothesis that the UK's exit from the EU has led to a differentiated reduction in the contribution of different innovative components on competitiveness. The main objective of our analysis aims to quantify / rank the intensity of the correlation between the different indicators of innovation and competitiveness, on the whole EU-27 compared to EU-28 in 2019 (the year before Brexit). In order to determine the intensity of the correlations, we calculated the correlation coefficients and the coefficients of determination between the variables of innovation and economic competitiveness, and then, to identify management priorities, we analyzed comparatively the values for EU-28 and EU-27 for each category of indicators. Our findings show that the strongest correlations are between competitiveness and R&D expenditures, respectively high-tech exports to both the EU-28 and the EU-27, but the most visible impact of Brexit was on the R&D personnel, an indicator whose contribution to competitiveness recorded the most significant decrease post-Brexit. In this context, the original contribution and practical implications of this research are given by the identification of priorities for intervention in the field of innovation to improve competitiveness in the EU-27 post-Brexit.