The German Corona-Warn-App (CWA) is one of the most controversial tools to mitigate the Corona virus spread with roughly 25 million users. In this study, we investigate individuals’ knowledge about the CWA and associated privacy concerns alongside different demographic factors. For that purpose, we conducted a study with 1752 participants in Germany to investigate knowledge and privacy concerns of users and non-users of the German CWA. We investigate the relationship between knowledge and privacy concerns and analyze the demographic effects on both.Our results indicate that knowledge about the CWA significantly reduces the privacy concerns about it. Non surprisingly, users have far lower privacy concerns than non-users, but they also have more knowledge about the app. We also find a positive significant effect of education and income and a small negative effect of age on the participants’ knowledge. Furthermore, we find a significant negative effect of income and education on the privacy concerns. Our study has important implications for political decision-makers aiming at increasing adoption rates for helpful technologies to mitigate the severe effects of the pandemic. Most relevant here is to acknowledge the results regarding education, knowledge, privacy concerns and CWA use and devise effective strategies to reach certain groups in the society which are currently not using the CWA.