The invention relates to a measuring device for monitoring space relative deformation caused by space relative movement of an upper disc and a lower disc of an in-situ rock joint plane in the wild. The measuring device consists of an upper fixing rod, an upper fixing screw bolt, an upper telescopic rod, an upper fixed regulating screw bolt, an upper regulating rod, an upper connecting seat, an upper locking screw bolt, a lower fixing rod, a lower fixing screw bolt, a lower telescopic rod, a lower fixed regulating screw bolt, a lower regulating rod, a lower connecting seat, a lower locking screw bolt, a
normal displacement measuring rod, a telescopic spring, an outer sleeve, rolling balls, a sealing cap, a dial and a support rod through assembling connection. The device is respectively fixed with the upper disc rock and the lower disc rock of the joint plane through the upper fixing rod and the lower fixing rod, in addition, the
normal displacement measurement is realized through the telescopic effect of the
normal displacement measuring rod, and the plane deformation measurement is realized through the movement of the lower end part of a normal deformation measuring rod on the dial, so the measurement on the space relative deformation between the upper disc and the lower disc of the joint plane can be realized, and the measuring device has the
advantage that the space relative deformation value of the upper disc and the lower disc of the rock joint plane is directly obtained.