PURPOSE: To obtain a high frequency transformer utilizing a metal core for high frequency transformer having a flexible structure ensuring adjustment of, inductance by using a threaded metal core for the side surface of a cylindrical piece formed by pressing metal powder having kneaded a binder or binding the metal powder by heat treatment after the molding compression.

CONSTITUTION: The upper part of a bobbin 3 implanting terminals 6 at the lower end thereof is wound by a coil 2, this bobbin 3 is housed within a shield case 5 having a mold body 4 at the internal surface and the center of this bobbin 3 is screwed with a metal core 1 for varying inductance. This metal core 1 for varying inductance can adjust inductance by inserting an adjusting driver from an aperture 7 provided at the ceiling surface of a shield case 5 and rotating the core using a driver groove provided at the end surface of the metal core 1 for varying inductance.