With the advent of sociological theory, society started to be perceived as a different kind of reality, existing by its own laws as an independently functioning whole. However, from the beginning, there was no consensus among sociologists as to the nature of this totality. Are social wholes merely theoretical constructs or do they exist in reality? The separation of the social and non-social elements of social wholes, as well as the social and non-social systems was also problematic. This problem particularly concerns the interrelationships of the social system, culture, politics, economics and other systems. The holistic, systemic description of social life in sociology has a long history. Sociology has dealt intensively with the question of “systems” and much has been written on the subject. We are confronted with many different systemic perspectives In sociological theory, the notion of “social system” has various meanings and, needless to say, a full presentation of its understanding in sociology remains beyond the scope of this manuscript. The aim of the article is to analyse the ways of interpreting the notion of the system in its classical sociological models: mechanistic and organic, and to indicate the contemporary changes resulting from the spread of the new theory of systems and the new understanding of the social system. The latter is related not only to the new understanding of the subject that sociology deals with, but also to the new understanding of sociology as a science.