An anode and a secondary battery capable of improving the charge and discharge efficiency are provided. The anode includes an anode current collector, and an anode active material layer provided on the anode current collector. The anode active material layer has a plurality of anode active material particles containing at least one of a simple substance of silicon, a compound of silicon, a simple substance of tin and a compound of tin, and has a coat containing an oxo acid salt in at least part of the surface of the anode active material particles.