The utility model discloses an inlet guide-bush device of a cone-type piercer and relates to seamless steel pipe production equipment, solving the technical problem that bite of tube blanks are influenced due to machining and assembling errors of existing inlet guide bushes of piercers. The inlet guide-bush device comprises a guide bush body consisting of a first guide bush section, a second guide bush section, a guide bush seat, a guide bush gland, a flat key and a guide bush support. The guide bush support is connected with a wedge regulator which is composed of a left wedge, a right wedge, a first positioning screw, a stud, an upper wedge, a lower wedge, a second positioning screw and a regulating gasket and a locking device which is composed of a lock block, a swing rod, a pin, a locking hydraulic cylinder, a shaft sleeve and a wedge. The inlet guide-bush device has the advantages of simple and compact structure, convenience in regulation, capability of facilitating tube blank bite and quick changing of the guide bushes.