A nonaqueous electrolyte secondary battery comprising: a positive electrode, a negative electrode, a separator disposed between the positive electrode and the negative electrode, and an electrolyte solution containing a supporting salt having ionic conductivity, wherein the positive electrode comprises a composition containing components (a) and (b) below and satisfying a requirement (α) below, and wherein the negative electrode contains metal lithium and at least one selected from materials capable of lithium ion insertion/desorption: (a) an electrically conductive polymer selected from a group consisting of polypyrrole, polyaniline, polythiophene, polyisothianaphthene, polyphenylene sulfide, poly(3,4-ethylenedioxythiophene) and derivatives of polypyrrole and polyaniline; (b) a lithium salt formed by substituting a part of a polyanionic acid with lithium, the polyanionic acid is at least one selected from the group consisting of polyacrylic acid, polymethacrylic acid, polyvinylbenzoic acid, polyallylbenzoic acid, polymethallylbenzoic acid, polymaleic acid, polyfumaric acid and polyglutamic acid; and characterized in that (α) a molar ratio of a lithium element content in the component (b) to a content of at least one selected from a nitrogen element and a sulfur element involved in a charge/discharge reaction in the component (a) is 0.3 to 1.0. a positive electrode, a negative electrode, a separator disposed between the positive electrode and the negative electrode, and an electrolyte solution containing a supporting salt having ionic conductivity, wherein the positive electrode comprises a composition containing components (a) and (b) below and satisfying a requirement (α) below, and wherein the negative electrode contains metal lithium and at least one selected from materials capable of lithium ion insertion/desorption: (a) an electrically conductive polymer selected from a group consisting of polypyrrole, polyaniline, polythiophene, polyisothianaphthene, polyphenylene sulfide, poly(3,4-ethylenedioxythiophene) and derivatives of polypyrrole and polyaniline; (b) a lithium salt formed by substituting a part of a polyanionic acid with lithium, the polyanionic acid is at least one selected from the group consisting of polyacrylic acid, polymethacrylic acid, polyvinylbenzoic acid, polyallylbenzoic acid, polymethallylbenzoic acid, polymaleic acid, polyfumaric acid and polyglutamic acid; and characterized in that (α) a molar ratio of a lithium element content in the component (b) to a content of at least one selected from a nitrogen element and a sulfur element involved in a charge/discharge reaction in the component (a) is 0.3 to 1.0. (a) an electrically conductive polymer selected from a group consisting of polypyrrole, polyaniline, polythiophene, polyisothianaphthene, polyphenylene sulfide, poly(3,4-ethylenedioxythiophene) and derivatives of polypyrrole and polyaniline; (b) a lithium salt formed by substituting a part of a polyanionic acid with lithium, the polyanionic acid is at least one selected from the group consisting of polyacrylic acid, polymethacrylic acid, polyvinylbenzoic acid, polyallylbenzoic acid, polymethallylbenzoic acid, polymaleic acid, polyfumaric acid and polyglutamic acid; and characterized in that (α) a molar ratio of a lithium element content in the component (b) to a content of at least one selected from a nitrogen element and a sulfur element involved in a charge/discharge reaction in the component (a) is 0.3 to 1.0.