Abstract A superhydrophobic cotton fabric was prepared by dip-coating TiO2 for four times and subsequent surface modification with n-octadecylthiol (ODT). The surface morphology, crystal structure and chemical composition are studied by SEM, XRD, and XPS, respectively. Water contact angle on the superhydrophobic cotton fabric is approximately 151° and the glide angle is less than 20°. The results show that two factors of higher surface roughness and lower surface free energy play a crucial role for the formation of the superhydrophobicity. Finally, the formation mechanism of superhydrophobicity on the cotton fabric was discussed on the basis of Wenzel's and Cassie's theory.