A quick adjustment mechanism for spacing of probe modules, comprising: an upper frame, provided with upper guide rails on two opposite sides thereof and a mounting bracket; multiple probe holders, arranged in the length direction of the upper guide rails, two ends of each probe holder being respectively slidably connected to a corresponding upper guide rail; characterized in that: the mounting bracket is provided with a through slot arranged in a length direction of the upper guide rails; wherein the quick adjustment mechanism further comprises a pressing assembly, comprising a push rod movably installed on each probe holder along a vertical direction and slidably installed on the through slot along the length direction of the upper guide rail, a pressing plate connected to an outer circumference of the push rod and located between the mounting bracket and the probe holders, and an elastic member sleeved on the push rod and elastically supported between the pressing plate and the mounting bracket to provide an elastic force for actuating the pressing plate to press the probe holder, so as to lock the probe holder on the upper frame at a locking state; and a positioning adjustment tool, located below the push rod and configured to lift up the push rod under a jacking mechanism to separate the pressing plate from the probe holder, so as to make the probe holder to be at an unlocked state and capable of sliding on the through slot. an upper frame, provided with upper guide rails on two opposite sides thereof and a mounting bracket; multiple probe holders, arranged in the length direction of the upper guide rails, two ends of each probe holder being respectively slidably connected to a corresponding upper guide rail; characterized in that: the mounting bracket is provided with a through slot arranged in a length direction of the upper guide rails; wherein the quick adjustment mechanism further comprises a pressing assembly, comprising a push rod movably installed on each probe holder along a vertical direction and slidably installed on the through slot along the length direction of the upper guide rail, a pressing plate connected to an outer circumference of the push rod and located between the mounting bracket and the probe holders, and an elastic member sleeved on the push rod and elastically supported between the pressing plate and the mounting bracket to provide an elastic force for actuating the pressing plate to press the probe holder, so as to lock the probe holder on the upper frame at a locking state; and a positioning adjustment tool, located below the push rod and configured to lift up the push rod under a jacking mechanism to separate the pressing plate from the probe holder, so as to make the probe holder to be at an unlocked state and capable of sliding on the through slot. the mounting bracket is provided with a through slot arranged in a length direction of the upper guide rails; wherein the quick adjustment mechanism further comprises a pressing assembly, comprising a push rod movably installed on each probe holder along a vertical direction and slidably installed on the through slot along the length direction of the upper guide rail, a pressing plate connected to an outer circumference of the push rod and located between the mounting bracket and the probe holders, and an elastic member sleeved on the push rod and elastically supported between the pressing plate and the mounting bracket to provide an elastic force for actuating the pressing plate to press the probe holder, so as to lock the probe holder on the upper frame at a locking state; and a positioning adjustment tool, located below the push rod and configured to lift up the push rod under a jacking mechanism to separate the pressing plate from the probe holder, so as to make the probe holder to be at an unlocked state and capable of sliding on the through slot.