The article is dedicated to analyzing the impact of illegal migration on Poland’s security, taking into account both international and national contexts. The first part provides a definition and classification of migration, including the differences between legal and illegal migration, and discusses the causes of this phenomenon, such as armed conflicts, poverty, and the search for better living conditions. The second part of the text focuses on Poland’s historical migration background, highlighting the changing migration patterns over the years. The authors also address the situation on Poland’s eastern border, which is particularly vulnerable to illegal crossings. The following section discusses the threats associated with illegal migration, such as organized crime, human trafficking, drug and arms smuggling, and the potential risks related to terrorism. It also touches upon issues of social integration, challenges for the healthcare and social systems, and potential social tensions. In the concluding part of the paper, the authors discuss political and administrative responses to the issue of illegal migration. They emphasize the need for integrated actions at both the national and international levels, including strengthening border controls and cooperating with other countries and international organizations. Recommendations are also presented regarding future actions aimed at more effective migration management and minimizing associated threats. A research problem was formulated within the discussed topic: What are the main threats to Poland’s security resulting from illegal migration? The formulated hypothesis is: The main threats to Poland’s security resulting from illegal migration include an increase in organized crime, terrorism risks, and social tensions caused by difficulties in integrating migrants. To address the research question, methods such as critical literature analysis, analysis of legal acts and documents, and reliable online sources were used.