A primary battery includes: a positive electrode including a positive electrode collector composed of a porous conductor, and a porous positive electrode layer disposed on the positive electrode collector, oxygen taken from outside of the primary battery through the positive electrode collector being allowed to diffuse into the porous positive electrode layer; a negative electrode including a negative electrode collector composed of a porous conductor, and a porous negative electrode layer disposed on the negative electrode collector, the porous negative electrode layer including lithium nitride composed of lithium and nitrogen, nitrogen generated during discharge being allowed to diffuse into the porous negative electrode layer; and a nonaqueous electrolytic solution disposed between the positive electrode and the negative electrode, the nonaqueous electrolytic solution containing a lithium salt.