Nanotechnology is a rapidly expanding interdisciplinary field that is frequently considered as a new industrial revolution. Among various nanoparticles, zinc oxide nanoparticles (ZnO NPs) are adaptable semiconducting inorganic materials with two main crystal structures. The use of plant extracts for synthesising metal oxide nanoparticles offers a promising alternative to traditional chemical methods. This study aimed to synthesis eco-friendly zinc oxide nanoparticles using Citrus reticulata (orange) peel powder with two zinc precursors. Cotton fabrics coated with ZnO-1 and ZnO-2 nanoparticles, along with cross-linking agents, showed improved overall performance compared to the control. The treated fabrics displayed fibre swelling, increased weight and thickness (especially with citric acid treatments ZAC1 and ZAC2), and better crease recovery without added stiffness. Tensile strength, elongation, water repellency and colour strength also improved due to nanoparticle deposition, enhancing physical and mechanical properties of the fabric.