The invention relates to a nanometer material reinforced cotton fabric crease-resistant finishing liquid and an application of the crease-resistant finishing liquid. The finishing liquid comprises a nanometer material, a crease-resistant finishing agent, a catalyst, an initiator, a strong protective agent and a solvent-water. The finishing method comprises the steps of dipping a cotton fabric into the crease-resistant finishing liquid for 3-5min; respectively dipping and rolling for two times, wherein the liquid entrainment rate is 80-85%; drying and baking. The nanometer material reinforced cotton fabric crease-resistant finishing liquid is superior to a conventional crease-resistant finishing liquid and has the characteristics that the tensile strength of the fabric can be remarkably improved, the problem that the strength of an existing crease-resistant finishing fabric is reduced can be obviously improved, and the nanometer material reinforced cotton fabric crease-resistant finishing liquid and the application of the crease-resistant finishing liquid have wide application prospects and market prospects.