Abstract: The partially depleted SOI （PDSOI） NMOSFET and CMOSFET’s latch characteristics are studied in this paper. A holding voltage measure method by bulk electrode trigger PDSOI NMOSFET latch effect is proposed. We use this method measured out the holding voltage of NMOSFET/CMOSFET transistors with different gate width,gate length,bulk contact types,and the influence of the channel implantation condition and temperature.