In this paper we present a review of the application of X-ray computed tomography in soil science, a modern technique for structural analysis. The quantification of internal soil structure is the key in understanding the processes that lead to its development. The current analytical and traditional methods for exploring soil structure do not fully cover the needs of the researchers, in order to characterize the soil system and its properties. In the last decades, X-ray computed tomography has provided a non-destructive means in order to observe and quantify soils in 3D. It has been used in researches regarding the spatial distribution of soil pores, bulk density, macropore network structure, layer detection, permeability, calculated fractal properties, solute breakthrough, root system development etc. Compared to other analysis methods, the short time requiered for a CT scan (within the order of minutes) and the accuracy of the data provided, recommend this technique for the characterization of soil systems.