The invention discloses a fixture used for on-site detection of an inter-layer bonding condition of white and black pavement. The fixture includes a force transmission structure, a forging die main-body, clamping pieces, ropes, a bearing and a non-return ratchet mechanism. The force transmission structure includes a force transmission rod. Up-down penetrating rope threading holes are arranged at astep surface of an upper part of the forging die main-body. An inner ring of the bearing is arranged in a fixed sleeving manner on the force transmission rod. Upper parts of inner sides of the clamping pieces are in detachable clamping connection with an outside surface of a lower part of the forging die main-body. Two adjacent clamping pieces engage with each other through a cogging structure. Afirst end of a rope is fixed at the bottom of one of the clamping pieces. Second ends of the ropes are fixed at a lower part of an outer ring of the bearing. An inner ring of the ratchet is fixed atan upper part of the outer ring of the bearing. A lower end of a torsion spring is fixed at the upper part of the forging die main-body. An upper end of the torsion spring is fixed at a first end of apawl. A second end of the pawl is used for unidirectional position limiting on the ratchet. The fixture is characterized by not requiring use of epoxy resin AB glue, thus improving measurement accuracy, eliminating solidification time and grinding time of the epoxy resin AB glue, and improving work efficiency.