Provided is a cordless vacuum cleaner including a cleaner body including a first processor configured to control an operation of a first switching device connected to a signal line to transmit a first signal to a brush device through the signal line and receive a second signal from the brush device through the signal line, and the brush device including a second processor configured to control an operation of a second switching device connected to the signal line to transmit the second signal to the cleaner body through the signal line and receive the first signal from the cleaner body through the signal line.