Innovation is vital for each country’s economic growth. This paper comprises an analysis of the main indicators that characterize innovation activity in Romanian firms. Improving our knowledge of firms’ activities in aspects associated with their behavior related to innovation is important for monitoring the strengths and weaknesses of the national innovation systems. Our study on Romanian firms is based entirely on the published data by Eurostat (the Commission Innovation Survey – CIS), which centralizes data every two years, the last have been published at the end of 2016 (CIS 9) covering the period 2012-2014. From building and analyzing three main types of general innovation indicators related to firms’ innovativeness, including innovation inputs and outputs, our results show that the main weaknesses in business innovation persist over time and they consist of the extremely low share of innovative firms, a low level of business innovation expenditures and a high volatility of innovation performance based on creative effort resulted from R&D activities still concentrated in a few industries.