According to one embodiment, provided is a secondary battery including a negative electrode containing a titanium-containing oxide, a positive electrode, a separator between the negative electrode and the positive electrode, a first aqueous electrolyte, a second aqueous electrolyte, and a third aqueous electrolyte. The first aqueous electrolyte is held in the negative electrode and contains 0.001% by mass to 0.5% by mass of zinc ions. The second aqueous electrolyte is held in the separator and contains 1% by mass to 5% by mass of a first compound that includes a hydrophobic portion and a hydrophilic portion. The third aqueous electrolyte is held in the positive electrode.