Today, rapid and unpredictable changes in the economy, globalization, the technical revolution, competition intensification, the reviving of the service industry required rethinking the concept of corporate competitiveness. An important determinant of corporate successfulness consists in that knowledge and adequate information which positively contribute to the corporate value creation. Those intangible capital elements that play a crucial role in sustainable corporate value creation are intellectual capital. The knowledge, skills and competencies of managers and employees customer relations, the company's organizational structure are the main components of intellectual capital. Today, the software and the knowledge-based economies support the fact that the importance of intellectual capital has been growing in all sectors of the economy. The main aim of this study is to investigate the relationship between intellectual capital and corporate performance. To these, we carried out a comparative analysis of value added by intellectual capital for companies acting in different sectors from two neighbouring counties from Romania (Bihor) and Hungary (Hajdú-Bihar). The analysis is based on the financial statements for five years (2014-2018) of companies operating in agriculture, construction, manufacturing, wholesale trading, retail trade and transportation. We used the Value Added Intellectual Coefficient (VAIC) from Scorecard Methods as a measurement of intellectual capital. The investigation of the relationship between firms' performance and intellectual capital was performed using panel regression, where the established dependent variables were Operating Return on Assets (OROA), Operating Return on Sales (OROS) and the explanatory VAIC components: HCE, SCE, CCE. In the case of Romanian companies, a medium-strong correlation can be observed between OROA and VAIC components. In the case of Hungarian firms also a medium-strong correlation can be observed between OROS and VAIC components.