A high sensitivity leakage current detection interrupter (LCDI) includes a shielded wire, a current leakage detection unit, and a tripping mechanism. A live core and a neutral core of the shielded wire are respectively wrapped in two conductive shell wires. The current leakage detection unit includes a pair of rectifying diodes reversely connected in series between a live line and a neutral line of a power supply, a voltage dropping resistor, thyristors, and resistor-capacitor (RC) voltage dropping filter circuits. The tripping mechanism includes control units with on/off respectively controlled by the thyristors. When either of the thyristors is turned on, the corresponding control unit is turned on, and the tripping mechanism is actuated to switch off the power supply.