The construction and operating characteristics of a pressurized laser‐triggered spark gap capable of switching voltages exceeding 10 kV with a risetime of less than 300 psec are described. Other desirable features are its low delay and jitter times (∼1 nsec), the ability to deliver rectangular pulses with less than 10% ripple during and after the pulse, and its simplicity of construction. The gap has been investigated using the output of either a single mode ruby laser or a mode‐locked neodymium‐glass laser as a trigger.