The article presents the problem of selected aspects of social security in Poland. A source of motivation to address the issue of social security for the author was the geopolitical situation related to the increase in the number of Muslim immigrants in Europe in recent years and the current COVID-19 epidemic. Counteracting the threats of a social nature has become one of the main activities of the state in the 21st century. Social security relates to a wide range of activities carried out by the public administration, NGOs and the local communities to guarantee decent living conditions. All of this constitutes a special kind of security, the lack of which directly interferes with the foundations of a nation’s existence. The aim of the study was to present issues related to the depopulation process affecting Poland and the demographically unfavourable changes taking place in modern families. The article presents the situation prior to the emergence of the COVID-19 epidemic. Undoubtedly, the COVID-19 epidemic will significantly affect social security, also in the demographic dimension. However, the overall impact of the epidemic can only be estimated after it has completely ceased. Conclusions included in the article were formulated on the basis of the analysis of statistical data of the Central Statistical Office. In addition, the author points out the consequences resulting from a long-term demographic collapse in the country.