The invention discloses a portable line fault indicator tester, which comprises a lithium battery pack, a battery monitor, an inverter, an operation panel, a controller, an alloy magnetic core, a primary coil, a secondary coil, a load resistor, a controllable short circuit switch, a first terminal, a second terminal and a copper bar. Through simulating a power failure scene, whether the line fault indicator fails can be effectively, safely and conveniently tested.