A bicycle communication adapter is provided with a voltage converting component, a signal converting component and a superimposing component. The voltage converting component is configured to convert a received voltage supplied from a bicycle electrical management system to a converted voltage suitable for at least one of a plurality of electric devices of a bicycle electrical system. The signal converting component is configured to convert a received signal outputted from a bicycle electrical management system into a converted signal compliant with a standard for power line communication. The superimposing component is configured to superimpose the converted signal converted by the signal converting component onto the converted voltage converted by the voltage converting component.