According to one embodiment, a secondary battery including a positive electrode, a negative electrode, and an electrolyte is provided. The negative electrode contains a negative electrode active material. The negative electrode active material includes titanium-containing metal oxide particles, an anatase type TiO2 phase, and a solid electrolyte phase. Each of the anatase type TiO2 phase and the solid electrolyte phase is disposed on at least a portion of a surface of the titanium-containing metal oxide particles. The electrolyte contains an electrolyte salt and water.