A fixing structure of a connector is disclosed. The connector includes an insert portion and multiple wires connected to the insert portion. The fixing structure includes a wire binding block, a lower shell and an upper shell disposed with multiple first engaging structures. The lower shell is disposed with multiple second engaging structures separately corresponding to the first engaging structures and connected with the upper shell to form a chamber for receiving the connector and form a wiring hole for being passed by the wires. The wires are extended from the insert portion toward the wiring hole to form a bend section and a curve section in the chamber. The wire binding block is fixed on the curve section of the wires and clamped by the upper shell and the lower shell through engagement of the first engaging structures and the second engaging structures.