Abstract: The characteristics of the pulsed plasma have been measured using the triple probe method, and the temporal evolution of the plasma characteristics has been diagnosed in a single pulse. Electromagnetism disturbance has been controlled by metal shield and battery power supply for oscillograph. A code has been made to deal with data of triple probe method based on Labview. According to the characteristics of mixed ion components and supersonic ion velocities for pulsed plasma, the theory of the triple probe has been revised. Results show that during the pulse discharge time, the electron temperature Te is between 2-4 eV and the ion density ni is between 1017-1018 m-3 at the high voltage extraction interface, which is consistent with Langmuir single probes results.