Composite connector

A composite connector that contributes to an improvement of workability for mating connectors with each other while preventing or reducing an increase in manufacturing cost is provided. A composite connector includes a first module including a first housing in which a first connector is exposed, and a second housing rotatable about the first housing, the second housing including a second connector, and a second module including a third connector, and a third housing including a fourth connector, the third connector being configured to be mated with and connected to the first connector. The composite connector is configured so that the second and fourth connectors are mated with each other in a state in which one of a projection and a recess that is formed in the second housing is mated with the other of the projection and the recess that is formed in the third housing.