The invention relates to a portable high-voltage nanosecond squarer which belongs to a medicinal device for inducing cancer cell apoptosis by using a high-voltage nanosecond square wave pulse electric field. The portable high-voltage nanosecond squarer mainly comprises a power supply system, a high-voltage direct current module, a low-voltage power supply, a pulse forming system and a pulse shaping and counting system. The portable high-voltage nanosecond squarer has output pulses with highest amplitude of 15kV, pulse width adjustment range of 50ns-1us, rising edge gradient of reaching 10ns and controllable recurrence frequency of 0.2-15Hz; and the quantity of the output pulses of the portable high-voltage nanosecond squarer can be set. The portable high-voltage nanosecond squarer can be adjusted in multiple-parameters (pulse amplitude, pulse width, recurrence frequency, pulse quantity and the like), large-range and flexible and independent way, and is beneficial to researching the optimal window parameter of the cancer cell apoptosis and promoting the cancer cell apoptosis as well as improving the cancer treatment effect. Meanwhile, the portable high-voltage nanosecond squarer has compact and light structure, reliable work, simple operation and convenient popularization and application, and can be widely applied to the treatment of various cancers.