In a transmission line, a first ground conductor pattern and a second ground conductor pattern are connected through a first interlayer connecting conductor, and the first ground conductor pattern and a third ground conductor pattern are connected through a second interlayer connecting conductor. A first signal conductor pattern includes a first bypassing pattern portion that bypasses the first interlayer connecting conductor, and a second signal conductor pattern includes a second bypassing pattern portion that bypasses the second interlayer connecting conductor. Bypassing directions of the first bypassing pattern portion and the second bypassing pattern portion are opposite to each other.