The invention relates to a method for preparing isosorbide through cellulose, and belongs to the preparation field of synthesizing renewable energy sources and chemicals by utilizing of biomasses. The method comprises a step of hydrolyzing the cellulose under a dual-function catalyst of metal-solid acid and adding hydrogen to obtain reaction liquid containing sorbitol, and a step of catalyzing and dehydrating the reaction liquid containing the sorbitol through the solid acid to obtain the isosorbide. According to the method, liquid acid does not need to be added, the reaction liquid containing the sorbitol does not need to be separated and purified, wherein the reaction liquid is obtained by hydrolyzing the cellulose and adding the hydrogen. The method has the advantages that raw material is the cellulose which is abundant, low in cost and environment-friendly, the yield of the isosorbide reaches up to 56.3%, the catalyst is easy to separate and recycle, a very valuable new channel is provided for transferring the cellulose into high value-added chemicals, and the method has a good industrialization application prospect.