Innovativeness is important for the success and performance of firms on both the domestic and international markets. The majority of firms with a solid foothold on the market acknowledge the need for innovation as the driving force of organic growth and the way to distinguish themselves from the competition. This paper is aimed at analyzing both the internal and external factors that support the innovativeness of companies and the impact of these factors on the performance of enterprises. The methodological framework of research is of a deductive nature and the existing theories of innovativeness were availed of for the purposes of research on these particular phenomena. By availing of survey responses from personnel directors, heads of HR departments, while also specialists of the field of HR among 179 enterprises from various sectors, evidence was established in the cases of (1) the positive relation between external factors and the internal processes supporting the innovativeness of companies, while also (2) the positive relation between external and internal factors supporting innovativeness and the market situation, economic efficiency and the development of companies. The herein paper makes a theoretical and empirical contribution in terms of research into the innovativeness of enterprises.