Abstract: A pressure switch. The switch includes a pressure sensor device adapted for receiving the input pressure and then moving the link rod due to the deformation caused by the input pressure. The switch includes a contact point fine-tuner having a first contact point controlled by the link rod, and is capable of separating or contacting a second contact point, and the contact point fine-tuner is mounted on a frame extended upwards from the pressure sensor device. The link rod of the pressure sensor device has a rotary plate, and the rotary plate includes a top leaning portion. By adjusting the position of the rotary plate on the link rod the controlling relationship between the first contact point of the contact point fine-tuner is attached to adjust different predetermined pressure values.