To provide an antenna-tuning transformer, capable of uniformly removing image frequencies of a wide-receiving band.

A tap (a) is drawn near from the maximum utilizing power level of a primary side winding wire N, while performing impedance matching with a load circuit as well and connected via an additional capacitor C' for DC cutoff to the winding start or end of a secondary side winding wire N3 of an antenna-tuning transformer T1 or a tap drawn to the winding wire N3. The secondary side winging wire N3 connects both ends to terminals 2 and 3 linked to an IC amplifier and inserts an AC bypass capacitor C" between the terminal 3 and a ground circuit. Thus, an LC resonance circuit is formed from a primary side input winding wire N1, a primary side tuning winding wire N2 and the secondary side winding wire N3 of the antenna-tuning transformer T1 and a variable capacitor C and a trap circuit with respect to image frequencies is formed.