Based on the laboratory full-scale tensile failure tests on four full-bonded GFRP anti-anchors socketed into rock, the interfacial adhesion and bearing capacity of the anchor on rock foundation were studied, from which the micro-failure mechanism of the anchor was revealed. The results show that the pull-out failure occurred in GFRP anti-floating anchor, attributing to the dilative shear failure from anchor thread's interfacial deterioration. The ultimate uplift bearing capacity of GFRP anti-floating anchor with diameter of 25 mm, concrete of M30, anchorage length of 1.3 m and 0.55 m, was 255 kN and 195 kN, respectively, indicating that the high bearing capacity of the anchor for anti-floating purpose. The average bond strength between GFRP anti-floating anchor and grouting body was between 2.41 MPa and 5.10 MPa, higher than the recommended values from Technical Code for Engineering of Ground Anchoring and Shotcrete Support"(GB 50086-2015).