The invention discloses a preparation method of a nanocellulose sensor electrode material. According to the preparation method, nanocellulose is combined with CuO/Cu2O, so that surface morphology of CuO/Cu2O is improved, a high specific surface area is obtained, surface active vacancy of CuO/Cu2O is regulated, and response ratio is increased; the electrode material prepared with the method is higher in sensitivity, wider in linear detection range and better in selectivity.