The aim of this study is to analyze the determinants of access to health-related information on the Internet and their influence on perceived knowledge of health-related topics in European countries. Referring to the European citizens’ digital health literacy survey and applying structural equation modelling hypotheses, the obtained results showed that assumption of acceptance of information and capacity level are the main determinants which have the biggest influence on the perception of access to health-related information on the Internet. The access to health-related information negatively determined the perceived level of knowledge about health-related topics, which reveals that people making more use of the information are more critical in assessing the level of their knowledge. People who evaluated their health status as poor stated that they knew about health-related topics less. Therefore, the high level of access to health-related information does not mean that people would assume having more knowledge about health-related topics.