Protective device with sensor and manufacturing method thereof

The invention provides a protector with a sensor, which is simple in structure and excellent in operability, and the appearance of the protector is not worsened. The protection device (30) is characterized in that one end side of an insert (50) is pressed in a manner of blocking a space part (33) arranged in a hollow part (12) of the protection device installed on a sliding door (1), the other end side of the insert (50) is provided with an insulation part (60) for insulating a connecting part (M) of leg parts (39a, 39b) of a resistor (39), and the insulation part (60), core wires (31, 32), the resistor (39), the leg parts and the connecting part are covered by an injection molding material together with the insulation part (60), the core wires (31, 32), the leg parts and the connecting part. The insulating portion has a flat plate shape, and only left and right end portions (61, 62) of the insulating portion are exposed from a surface of a portion covered by the injection molding material (K). An inner protr