A method of manufacturing a solid electrolyte battery includes a step of thermally pressing a composite layer including a positive electrode ink layer, an electrolyte ink layer and a negative electrode ink layer that are formed by coating a positive electrode ink, an electrolyte ink and a negative electrode ink. Further, the positive electrode ink, the electrolyte ink and the negative electrode ink contain a polymer electrolyte. By this method, it is possible to improve the flow of ions across respective interlayers of a positive electrode active material layer, a solid electrolyte layer and a negative electrode active material layer.