Provided is a method of manufacturing a nonaqueous electrolyte secondary battery. The method includes: forming an electrode assembly including a positive electrode plate and a negative electrode plate disposed with a separator interposed therebetween; arranging the electrode assembly and a nonaqueous electrolyte containing LiBOB (lithium bis(oxalato)borate) and LiPF2O2 (lithium difluorophosphate) inside an outer body; and configuring the concentration of the LiBOB to be larger than that of the LiPF2O2 and to be smaller than that of the LiPF2O2 by charge and discharge.