In this paper, to suppress the current filamentation and improve di/dt capability, a pulse width adjustable trigger method based on Marx generator for reverse blocking diode thyristor (RBDT) is proposed. The importance of trigger voltage pulse width for RBDT is firstly illustrated. The influence of the width of the voltage trigger pulse on RBDT is simulated in TCAD and verified by experiments. It is turned out that the turn-on delay time can be reduced when the width of voltage trigger pulse is shorter than 800ns. When the width of the voltage trigger pulse further increases, the turn-on delay time becomes saturated. It is shown in the simulations that wider trigger voltage pulse can suppress the current filamentation in RBDT. The simulation result is validated by comparative experiments with two different widths of voltage trigger pulse generated by Marx generator at different main voltages. The switching loss of RBDT triggered by voltage pulse width of 1000ns is smaller than that by voltage pulse width of 240ns under the same condition. Besides, RBDT triggered by voltage pulse width of 1000ns can even survive when the maximum di/dt per unit area is about 16.7kA/μs/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> at the main voltage of 970V. However, RBDT triggered by voltage pulse width of 240ns fails at the main voltage of 920V. Finally, the sensitivity of the proposed trigger method is verified.