A human body communication device includes an electrode, a matching circuit, a switch providing a first path electrically connected to the matching circuit and a second path electrically connected to the matching circuit, a sensor, in a first state, connected to the matching circuit through the switch, outputting a first sensing signal to the matching circuit, and outputting a second sensing signal when a difference between a signal generated from the matching circuit in response to the first sensing signal and the first sensing signal is greater than or equal to a threshold, a transmitter, in a second state, connected to the matching circuit through the switch, and outputting a data signal to the matching circuit, and a controller controlling the switch from the first state to the second state in response to receiving the second sensing signal from the sensor, in the first state.