In this article, a trigger unit has been implemented to generate a high-current-density electron beam from a pseudospark (PS) discharge-based electron gun. A trigger pulse power supply unit has been designed and developed to provide the seed electrons from the ferroelectric cathode (FEC). The FEC has been used inside the hollow cathode cavity of a single-gap PS discharge-based electron gun. The electron gun has been operated in the self-breakdown as well as the trigger-based breakdown mode. A comparative analysis has also been performed between self-breakdown and trigger breakdown modes with the developed trigger unit's help for different applied gap voltages ranging between 0 and 16 kV. The designed trigger unit is based on a high-voltage-gain isolated dc-dc converter and a pulse-forming network. It is compact and capable of generating a negative pulse of ~-5 kV with a pulsewidth of ~500 ns. It provides better control over PS discharge to produce a high-current-density electron beam.