A charger for portable terminal equipment, capable of distinguishing a nickel-hydride battery pack and a nickel-cadmium battery pack and of detecting an on-hook/off-hook condition even when the nickel-hydride battery pack is used. The charger includes a charging circuit, a pair of third charging terminals connected to the charging circuit and adapted to be selectively connected to either a pair of first charging terminals of the nickel-hydride battery pack or a pair of second charging terminals of the nickel-cadmium battery pack, and a third auxiliary terminal adapted to be selectively connected to either a first auxiliary terminal of the nickel-hydride battery pack or a second auxiliary terminal of the nickel-cadmium battery pack. The charger further includes a device for comparing a voltage at the third auxiliary terminal with a first reference voltage and detecting the on-hook condition or the off-hook condition of the portable terminal equipment, and a device for comparing the voltage at the third auxiliary terminal with a second reference voltage lower than the first reference voltage and distinguishing the nickel-hydride battery pack and the nickel-cadmium battery pack.