The paper presents the status quo of the cyber security of road tunnel control centres and a methodology how to assess the existing cyber security level. This methodology includes aspects on a threefold level: firstly technical aspects (e.g. technical equipment used in tunnels and control centres), secondly organizational aspects (e.g. access control to operation buildings or handling of remote maintenance of hardware and software) and thirdly personnel aspects (e.g. awareness with regard to so called social engineering and knowledge about first signs of cyber attacks). In order to achieve an improvement easily, a software application accompanied by a guideline for assessing and improving the existing cyber security level was developed. Related results were achieved in the framework of the research project “Cyber-Safe” which is funded by the German Federal Ministry of Education and Research (BMBF). The contributions of all members of the consortium are gratefully acknowledged.