A tunable radio frequency (RF) coupler and manufacturing method thereof are provided. The tunable RF coupler includes an insulating layer, a first transmission line and a second transmission line. The second transmission line is disposed corresponding to the first transmission line and the insulating layer is disposed between the first transmission line and the second transmission line. The second transmission line includes a plurality of segments separated from each other and arranged along the extension path of the first transmission line. At least one wire is configured to establish an electrical connection between at least two segments, such that the two segments are electrically conductive to each other through the wire.