A standard plane with large area and a precision moving stage are required to calibrate the parameters for the phase measurement profilometry (PMP) system in large view field. It does not suite on-line calibration because of the discommodity to tote the required plane and stage. A new method for on-line calibrating the parameters of PMP system accurately is introduced to solve this problem. An undersize calibrating plane is placed at several positions in available measurement volume randomly to acquire dense data points. The inner and external parameters of camera are estimated with the method used in photogrammetry. A global reference plane and several assistant planes are appointed. And then, the differences of height and phase in every tested position between the plane and their corresponding reference plane are calculated in division. Finally, the parameters of phase-height mapping are estimated with maximum likelihood estimate. In experiment the standard diviation of plane height measurement reaches 0.0433 mm. This method is suitable for calibrating the PMP system with large view field because only a small standard plane is required , the calibrating procedure is convenient and the result is highly accurate.