The irreversible electroporation tumor treatment technique has already achieved remarkable efficacy in clinical application. And recent studies have shown that the use of high-voltage nanosecond pulses in combination with low-voltage microsecond pulses can significantly improve the ablation efficacy. Therefore, this paper proposes a novel topology of synergistic pulse generator, which consists of two Marx circuits with IGBT and MOSFET as the main switches respectively. Through the flexible control of the switches, the synergistic pulse sequence composed of high-voltage nanosecond pulse and low-voltage microsecond pulse can be output. The operating principle, circuit simulation and prototype of the synergistic pulse sequence are studied. The result is an all-solid-state synergistic pulse generator with flexible and adjustable parameters by using semiconductor switches. And its performance was tested on a 100Ω resistance load. The nanosecond pulse parameters are as follows: voltage amplitude 0-15kV, pulse width 200ns-1μs. The microsecond pulse parameters are: voltage amplitude 0-5 kV, pulse width 10 μs-100 μs, which can meet the experimental requirements of collaborative pulse ablation of tumor.