An output protector for chargers connected to the output terminal of charger, comprising a MOS tube as electronic switch, a light switchover signal terminal, a power output V+ terminal, a power GND terminal connected to the source of the MOS tube, and a power output V− terminal connected to the drain of the MOS tube. The power output V+ terminal and power GND terminal are connected to the output terminal anode and cathode of charger respectively. The light switchover signal terminal is connected to the charging state signal output end of charger. The power output V+ terminal and power output V− terminal are connected to the anode and cathode of battery, and the output protector has a triode on-unit which drives the MOS tube after the power output V+ terminal and power output V− terminal are connected to the anode and cathode of battery respectively.