A derailleur comprises a base member, a chain guide, a link member, and a shaft member. The base member is configured to be attached to a bicycle frame. The chain guide comprises a first member and a second member. The first member includes a first connecting portion. The second member includes a second connecting portion to overlap the first connecting portion. The link member is configured to movably couple the chain guide to the base member. The shaft member is configured to couple the first connecting portion to the second connecting portion and configured to rotatably couple the chain guide to the link member.