A battery monitoring apparatus monitors a battery pack configured by a plurality of battery cells. The battery monitoring apparatus includes a main monitoring unit, a sub monitoring unit and a control unit. The main monitoring unit monitors a plurality of physical quantities indicating a battery state of the battery pack. The sub monitoring unit monitors a part of the physical quantities separately from the main monitoring unit. The control unit detects malfunction of the battery pack on the basis of at least one of a monitoring result of the main monitoring unit and a monitoring result of the sub monitoring unit.