Cyber defense is concerned with the protection of information in the search for fighting against attacks that violate the sovereignty and control of technological and computer resources. Given the research importance that this topic has acquired in recent years, the aim of this article is to examine the research trends in the study of cyber defense from a bibliometric analysis between 1992 and 2019. The methodology is based on a bibliometric analysis of 641 documents compiled from a search equation in Scopus, for this the quantity and quality indicators are calculated and emerging themes are recorded. The results show that the countries with more research in the field are: United States, China, India and United Kingdom. Additionally, the emerging themes in cyberdefense are: safety networks, computer crime, cybersecurity, decision making, malware and game theory.