The invention discloses a hydraulic expandable liner hanger provided with a double-safety releasing gadget. The hydraulic expandable liner hanger comprises an expansion base tube, an expansion cone and two hydraulic cylinders, wherein the expansion base tube, the expansion cone and the hydraulic cylinders are mounted on an inner tubing string in a sleeving manner sequentially; a ball socket and a ball
assembly re arranged in the top end of the expansion cone, and the upper end of a ball is connected with the lower end of one
hydraulic cylinder; a
liquid injection hole is formed in the top surface of the
hydraulic cylinder at the upper end; the upper end of the inner tubing string is connected with an upper
adaptor connector; the lower end of the expansion base tube is connected with a releasing
coupling; a
collet is mounted in the releasing
coupling in a sleeving manner, a releasing body is connected into the upper part of the
collet, and the lower end of the inner tubing string is connected into the upper part of the releasing body; an outer slide
bushing and an inner slide
bushing are mounted inside and outside the inner tubing string respectively in a matched and sleeving manner; a pressure relief hole is formed in one side wall of each of the inner slide
bushing, the outer slide bushing and the inner tubing string; a conical pin seat is connected into the lower end of the releasing body; a core tube is arranged in the conical pin seat and the releasing body in a matched manner, the upper end of the core tube is propped against the lower end of the inner slide bushing, and the lower part of the core tube is integrally connected with the conical pin seat through a
shear pin; a thrust disc is arranged in the lower end of the
collet and connected with the lower end of the core tube.