A triggering device (100) for an optical detection instrument and an optical detection instrument are provided. The triggering device may include: a triggering switch (1) configured to start an optical detection to emit a detecting light when the triggering switch is triggered, a hollow shaft (2) for accommodating an optical path, the hollow shaft being configured to allow the detecting light to pass through its cavity to reach an object to be detected, the hollow shaft and the triggering switch having a fixed relative position, and a sliding trigger (3) configured to move towards or away from the triggering switch with respect to the hollow shaft to trigger or reset the triggering switch. The triggering device can automatically start the detection operation of the optical detection instrument and stop the detection operation timely, by moving the sliding trigger with respect to the triggering switch. It can not only improve the triggering speed and efficiency of the triggering device, but also reduce the complication of the detection operation so as to avoid loss caused by faults of the triggering operation and resetting operation.