A compact nanosecond-pulse high peak power blue laser array was fabricated, achieving a peak output power of 300W using eight GaN based edge emitting lasers and stable operation without output power degradation under no active cooling. Based on theoretical equivalent circuit modeling of laser and GaN MOSFET, the effects of device capacitance and inductance on the high-current nanosecond pulsed drive signal during the switch on and off processes of nanosecond laser pulse driving were analyzed. Theoretical and experimental results verified that the kickback current is closely related to the parasitic parameters of the devices, and that suppressing parasitic inductance and increasing the current-limiting resistor in the circuit can reduce this reverse current. Furthermore, the thermal resistance of the laser was analyzed, and an aluminum nitride (AlN) ceramic heat sink was employed to lower the thermal resistance.