This Article analyses the structural comparativism and its implications for comparative public law. The term «structuralism» refers to various theories across the humanities, social sciences, and economics. When we refer to this approach, we focus on the structure and the relationship of the different components of legal institutions or «legal formants» existing within each legal system. The essay is divided into three parts. Part I analyses structuralism as a method. The structural comparison represents a methodological choice of theoretical nature and can be seen as a specialised application of functional comparison. Part II is devoted to the relationship between structuralism and legal science. Following the transformation of law in a structural way means doing multiple synchronous cuts, then comparing the systems. Finally, Part III highlights the development of structuralism in comparative private and public law, with particular attention to the dynamic approach.