Abstract: A system, apparatus and method for controlling an internal pressure of an inflatable pad are disclosed. The apparatus includes a control valve, a sensor, a driving device and a controller. The control valve is switched between statuses to selectively perform inflation and deflation of the inflatable pad. The sensor measures the internal pressure of the inflatable pad. The driving device is coupled to the control valve to blow air into the inflatable pad. The controller is coupled to the control valve for controlling the internal pressure at a predetermined pressure. Responsive to the present of a user, the controller deflates the inflatable pad within a deflation period and records the internal pressure during the deflation period. A characteristic curve is obtained representing the variation of the internal pressure corresponding to the user and an appropriate pressure is determined based on the characteristic curve.