The purpose of this thesis was to find out the state of cybersecurity in shipping. The main objective was to study what sort of networks are used onboard vessels and how secure they are. The second objective was to study Finnish officers’ IT skills and security awareness. Maritime IT legislation and guidelines from the IMO and classification societies are presented in this thesis. The vulnerabilities of various navigation devices are listed. The effect of onboard computers on vessel’s network are presented. IT education of seafarers in Finnish universities was investigated. The insurance coverages concerning cyberattacks, effect of automation on system security and the future development of maritime sector on cybersecurity were studied. Theory of both remote side and client side cyberthreats was researched. Network structures of two Finnish vessels were investigated for this thesis. The different devices in the network and IT practices of vessels are presented. A possible attack scenario against the first vessel’s network is described. Finnish officers’ IT skills were studied using a survey consisting of 26 questions. There was a total of 17 answers. The results were analysed in three categories: backgrounds, IT skills and security awareness. This thesis is partially incomplete as it was not possible to study the configurations of the vessels’ switches and firewalls. This subject should be studied further in the future. In general, the existing networks have potential to be secure but there is still room for improvement. The IT skills of the officers were better than initially expected but there were also some serious deficiencies. Training seafarers on cybersecurity should be made essential in the future. In addition, a concept of IT officer was considered in terms of education, skills and responsibilities.