This thesis aims to explore the connection between the physical law of entropy and the causes of the current ecological crisis. The research will consist of three parts. In the first part, the aim is to set the framework through the description of the origin, development, and definition of the entropy law in physics, primarily in thermodynamics. The second part presents extensions of the entropy notion to fields outside the original context, during which many deformations and simplifications occurred. In this part, the focus is on the application of the entropy law in explaining the causes of the ecological crisis, particularly in the work of the economist Nicholas Georgescu-Roegen – primarily his book The Entropy Law and the Economic Process – and in the works of Marxist ecologists inspired by him. In the last part, after examining the adequacy of the notion of entropy for the approach to the ecological crisis and, secondly, separating valuable elements from previously analyzed uses, I will explore the impact of capitalism on the emergence of the ecological crisis. In the end, the recent rehabilitation of dialectics of nature is taken as a positive answer to the challenges the crisis brings.