Circuit board assembly of current sensor and current sensor

The utility model relates to the technical field of current sensors, in particular to a circuit board assembly of a current sensor and the current sensor, and the circuit board assembly comprises a circuit board. The detection element is fixed on the circuit board through a contact pin and is positioned in the iron core of the current sensor; the protection piece is provided with an accommodating groove for accommodating the detection element and an avoiding structure for avoiding the contact pin of the detection element so as to enable the contact pin to be inserted and fixed on the circuit board; the protection part is additionally arranged, the detection element is firstly installed in the containing groove, the detection element and the protection part serve as a whole to be installed on the circuit board, the avoiding structure is used for the contact pin to penetrate through, installation of the detection element and the circuit board is not affected, and normal use of the detection element is not affec