To provide a radio frequency transformer and its use with which the cost of a circuit is reduced by reducing the area to be used or other functions can be set by providing the facility for other components to be easily mounted.

A radio frequency transformer has two master lines (1, 9) which constitute the transformer on at least four layers of a printed circuit. Two of the four layers correspond to each line. In one variant, the master lines are wrapped onto a cube. The layers corresponding to one line are interleaved with the layers corresponding to the other line. The transformer with such constitution as above has two input ports (5, 13), one (13) of which is connected to ground (21), and two output ports (19, 20).