Diplexer

The objective of the present invention is to provide a diplexer with which it is possible to restrict the complexity of conductor routing. The diplexer according to the present invention is provided with: a first filter circuit including a first loop inductor and a second loop inductor which form a first loop surface and a second loop surface; a second filter circuit provided adjacent to the first filter circuit; and a first via hole conductor which electrically connects an input and output terminal to the first filter circuit and the second filter circuit. The diplexer is characterized in that: the first loop surface faces the second loop surface in a state in which said first loop surface protrudes out in a first direction relative to the second loop surface; and in that the first via hole conductor is provided to a second direction side of the first loop inductor, said second direction being a direction from the first loop surface to the second loop surface, and the first via hole conductor overlaps the pa