Provided is a highly convenient communication device capable of detecting a communication error caused by an abnormality of a state of communication. A communication device capable of mutually communicating with an electrical device includes: a superimposed signal receiving unit that periodically receives a data signal related to the electrical device as a signal superimposed on an operation signal; a period determination unit that determines whether or not a communication error of the data signal detected by the superimposed signal receiving unit is able to be regarded as having occurred in a transition period of a value of the operation signal; and a state determination unit that determines a state of communication with the electrical device in accordance with the determination by the period determination unit.