The utility model discloses a novel current transformer that can install with electricity fast, first casing and second casing all are the setting of U type, the cylindricality groove has all been seted up to two terminal surfaces of first casing, the cylindricality inslot is inserted at the both ends of second casing to the terminal surface at both ends is inconsistent with the tank bottom in cylindricality groove, be equipped with the fixture block on the first casing, be equipped with the card on the second casing, when the cylindricality inslot is inserted at the both ends of second casing, in the fixture block is embedded into the card, with first casing and second casing joint, second casing inboard is equipped with the conflict subassembly inconsistent with external cable. The utility model discloses a novel current transformer that can install with electricity fast, through the setting of first casing, second casing, cylindricality groove, fixture block and card, just can be effectual the realization mutual -inductor can dismantle the connection fast, and the setting through the conflict subassembly just can be effectual and external cable is inconsistent, fix external cable with the mutual -inductor on.