To increase inductance while avoiding the expansion of a filter element which is configured by winding a band-like conductor around a band-like insulator while overlapping them with each other.

This filter element comprises: a coil section 5D formed by winding signaling band-like conductors 9a, 9b ground band-like conductors 8a, 8b which are provided side by side, and grounding band-like conductors 8a, 8b which are disposed while facing the signaling band-like conductors 9a, 9b, around a band-like insulator 7b; an input terminal 2a and a lead wire 11 which are connected to the signaling band-like conductors 9a, 9b and pulled outside; an output terminal 3a which is connected the signaling band-like conductor 9a and pulled outside; a lead wire 12 which is connected to the signaling band-like conductor 9b and pulled outside; a lead wire 15 which is connected to the grounding band-like conductor 8a and pulled outside; a lead wire 16 which is connected to the grounding band-like conductor 8b and pulled outside; and a grounding terminal 4a which is connected to the grounding band-like conductor 8b and pulled outside, wherein the lead wires 11, 12 and the lead wires 15, 16 being connected with each other.