The insect cuticle is a multifunctional biological material. One of its striking characteristics is the wide range of its mechanical properties. The elastic modulus of insect cuticle, for example, covers a range of more than eight orders of magnitude [1]. Why do cuticle properties vary so dramatically? To address this question, researchers have used a set of different testing methods to measure the properties of cuticle specimens, which have been selected from various body parts across a variety of insect species and often preserved/prepared in different ways [2,3]. However, almost all these factors can influence the obtained data. Hence, the literature data cannot be simply compared with each other, and no solid conclusion can be drawn regarding the mechanisms that underlie the property variations in the cuticle. To fill this gap in the literature, our studies are focused on two key questions. First, how do the mechanical properties of insect cuticle differ in a single species when all testing conditions are kept constant? Second, what are the mechanisms behind the wide range of cuticle properties? Using a combination of scanning electron microscopy (SEM), micro-computed tomography (micro-CT), confocal laser scanning microscopy (CLSM) and nanoindentation, we performed one of the most comprehensive studies to date, where we simultaneously investigated the microstructure, sclerotization and the elastic modulus of locust cuticle from different body parts. We have shown that, in the desert locust Schistocerca gregaria, the elastic moduli of tibiae, femora and compound eyes range from 0.5 GPa to 8 GPa [4-7]. This property change can be explained almost fully by the differences in the microstructure and sclerotization of the investigated specimens. We expect that our results will help to better understand the complex structure–material–function relationship in insect cuticle. In addition, the detailed data obtained might be potentially interesting for the biomimetic development of strong composite materials for various applications.