A nonaqueous electrolyte secondary battery according to the present invention includes: an electrode body including a positive electrode including a positive-electrode active material layer; an external terminal connected to the electrode body; a nonaqueous electrolyte including a gas generant, and a current interrupt device. A content of the gas generant is at least 4 mass %. The positive-electrode active material layer includes, as a positive-electrode active material, a complex oxide containing at least zirconium (Zr) and calcium (Ca) as constituent elements. When a sum total of metal elements, except metal that becomes a charge carrier, in the complex oxide is 100 mol % in terms of a mole percentage, the complex oxide contains Zr from 0.1 mol % to 0.5 mol % inclusive and Ca from 0.1 mol % to 0.3 mol % inclusive.