To provide an inspection method of battery in which proper good-product reference values are set based on a measurement result of each battery of an inspection lot while avoiding an effect which the variations in respective batteries forming the inspection lot give to the measurement precision, and judgement of a defective battery can be made precisely based on the good-product reference values.

The inspection method of battery is provided with a process in which a voltage drop amount ΔV due to self-discharge is calculated with respect to each of a plurality of batteries 1, 1, ... forming an inspection lot, a process in which the good-product reference values for judging the acceptability of the batteries are set based on the calculation result of the voltage drop amount ΔV of each battery 1, 1, ... for every inspection lot, and a process in which, with respect to each of the batteries 1, 1, ..., the battery 1 in which the difference between the good-product reference values and the voltage drop amount ΔV exceeds a prescribed good-product threshold d is judged as a defective product. The method is provided with a process in which each batteries 1, 1, ... are classified based on a manufacturing lot and the inspection lot is formed of each batteries 1, 1, ... in the same manufacturing lot.