A floor hinge hidden in a door panel, the door panel having a bottom provided therein with a receiving chamber, the floor hinge comprising: a base fixed to a ground; a body fixed to the receiving chamber from inside and having an oil storage space for storing a hydraulic oil and an axle bore in perpendicular communication with the oil storage space; an axle pivotally disposed in the axle bore of the body and having a spindle and an eccentric cam disposed at the spindle, the spindle having an end protruding out of the axle bore and connected to the base; and a damping unit disposed in the oil storage space of the body and abutting against the eccentric cam of the axle so as for the damping unit to be pushed by the eccentric cam to thereby compress the hydraulic oil for generating a resistance to door-opening and door-shutting; the base has a fixing plate, an adjusting plate, and a plurality of adjusting screws (23,24), the fixing plate being fixed to the ground, characterized in that the fixing plate has a recess, and forms a plurality of screw holes at a periphery of the fixing plate and in communication with the recess, wherein two screw holes are disposed on two opposing long sides of the fixing plate respectively and two screw holes are disposed on two opposing short sides of the fixing plate respectively, the adjusting plate being disposed in the recess of the fixing plate and connected to the spindle of the axle, and the plurality of adjusting screws (23,24) being disposed in the plurality of screw holes, respectively, to abut against the adjusting plate and thereby adjust a position of the adjusting plate relative to the fixing plate, and in that both the recess of the fixing plate and the adjusting plate are rectangular, and dimensions of the adjusting plate are less than dimensions of the recess of the fixing plate. a base fixed to a ground; a body fixed to the receiving chamber from inside and having an oil storage space for storing a hydraulic oil and an axle bore in perpendicular communication with the oil storage space; an axle pivotally disposed in the axle bore of the body and having a spindle and an eccentric cam disposed at the spindle, the spindle having an end protruding out of the axle bore and connected to the base; and a damping unit disposed in the oil storage space of the body and abutting against the eccentric cam of the axle so as for the damping unit to be pushed by the eccentric cam to thereby compress the hydraulic oil for generating a resistance to door-opening and door-shutting; the base has a fixing plate, an adjusting plate, and a plurality of adjusting screws (23,24), the fixing plate being fixed to the ground, characterized in that the fixing plate has a recess, and forms a plurality of screw holes at a periphery of the fixing plate and in communication with the recess, wherein two screw holes are disposed on two opposing long sides of the fixing plate respectively and two screw holes are disposed on two opposing short sides of the fixing plate respectively, the adjusting plate being disposed in the recess of the fixing plate and connected to the spindle of the axle, and the plurality of adjusting screws (23,24) being disposed in the plurality of screw holes, respectively, to abut against the adjusting plate and thereby adjust a position of the adjusting plate relative to the fixing plate, and in that both the recess of the fixing plate and the adjusting plate are rectangular, and dimensions of the adjusting plate are less than dimensions of the recess of the fixing plate.