The adder topology solid state modulator is a device that uses insulated gate bipolar transistors (IGBTs) to discharge the stored energy of capacitors to generate high voltage pulses. Compared with pulse forming network (PFN) type modulator, it has lots of advantages such as modularity, good stability, and long lifespan. However, the normal operation of IGBT requires the use of gate drive circuit to amplify the control signal, and the performance of the drive circuit directly affects the switching characteristics of the IGBT, ultimately affects the quality of pulse voltage, especially the turn-on jitter index of the drive circuit, which is one of the key factors affecting the pulse voltage repetition precision. Based on the operating characteristics of IGBT in the adder topology solid state modulator, the drive circuit was studied with the goal of improving pulse voltage repetition precision. The impact of turn-on jitter on voltage repetition precision was analyzed, the design principle was introduced, the drive circuit board was developed, and its working performance was experimentally tested using a discharge module. The test results indicate that the turn-on jitter of the drive circuit is 300 ps, which is three times better than commercial driving circuits. At the charging voltage of 1 kV, the discharge module discharges on a 0.5 Ω load, forming a pulse voltage with the rise time of 500 ns and the peak-to-peak value of turn-on jitter below 5 ns. When the desaturation fault occurs, the drive circuit can turn off the IGBT within 4 µs. This drive circuit meets the working requirements of high pulse repetition precision solid state modulators.