A low-cost chemical co-precipitation method was used to prepare chromium zinc oxide (Cr/ZnO) nanocombs. The structural, elemental composition, and morphological architectures of the nanocomposite were characterized using XRD, EDX, XPS, and SEM techniques. The analysis confirmed the incorporation of Cr3⁺ into the ZnO framework to form a homogenous nanocomb structure. The Cr/ZnO nanocombs exhibited small particle size, large surface area, and high aspect ratio, which are beneficial for numerous biological fields. Histological changes in the midgut of 5th instar nymphs of desert locust, Schistocerca gregaria (Orthoptera: Acrididae), treated with the nanoparticles were detected using light and transmission electron microscopy (TEM). High concentration treatment resulted in distortion of the brush borders of the microvilli and defective epithelial columnar cells. The muscle layer was distorted, with the longitudinal muscle layer absent 72 h after treatment. At the lowest concentration, defective microvilli were observed in some regions, and the epithelial columnar cells underwent changes where the muscle layer was also distorted.