A lithium primary battery includes a wound electrode body obtained by winding a sheet-like positive electrode, a sheet-like negative electrode, and a separator interposed between the positive electrode and the negative electrode, and a nonaqueous electrolyte solution. The positive electrode includes manganese dioxide as a positive electrode active material. The negative electrode includes at least one selected from the group consisting of metallic lithium and lithium alloys, and has a first principal surface and a second principal surface opposite to the first principal surface. An entire surface of each of the first principal surface and the second principal surface faces the positive electrode. A total area of the first principal surface and the second principal surface is 100 cm2 or more and 180 cm2 or less.