B-Line is a vocaloid artist from Japan. The name has also been used by a Japanese voca-rock producer called りょうた, and the available information identifies B-Line as a person rather than a band.

The name is associated with mash-up work and with music that combines material from current and older songs. It is also linked to original songs and cover versions. The artist is identified with the group name osuと愉快な仲間たち.