A biosignal measurement device, comprising: a biosignal processor configured to process a biosignal; and an electrode unit configured to sense the biosignal, the biosignal processor comprising: a first signal connector capable of removably attaching to the electrode unit, wherein the first signal connector is configured to receive the biosignal from the electrode unit; a power supplier configured to supply power to the electrode unit through a first power connector in response to the power supplier being connected to the electrode unit; a signal processor configured to differently process the biosignal received by the first signal connector based on whether power is supplied to the electrode unit; and the electrode unit comprising: at least one active electrode configured to connect with the biosignal processor, wherein the biosignal is sensed through at least one metal electrode being a direct contact type electrode, when the biosignal processor and the electrode unit are not connected such that no power is supplied through the first power connector to the electrode unit, and wherein the biosignal is sensed through the at least one active electrode being a capacitive coupling active electrode, when the biosignal processor and the electrode unit are connected by the first power connector and a respective second power connecter of the electrode unit such that power supplied from the power supplier is provided to the at least one capacitive coupling electrode; and a second signal connector capable of removably attaching to the first signal connector of the biosignal processor, wherein the second signal connector is configured to transfer the biosignal to the biosignal processor. a biosignal processor configured to process a biosignal; and an electrode unit configured to sense the biosignal, the biosignal processor comprising: a first signal connector capable of removably attaching to the electrode unit, wherein the first signal connector is configured to receive the biosignal from the electrode unit; a power supplier configured to supply power to the electrode unit through a first power connector in response to the power supplier being connected to the electrode unit; a signal processor configured to differently process the biosignal received by the first signal connector based on whether power is supplied to the electrode unit; and a first signal connector capable of removably attaching to the electrode unit, wherein the first signal connector is configured to receive the biosignal from the electrode unit; a power supplier configured to supply power to the electrode unit through a first power connector in response to the power supplier being connected to the electrode unit; a signal processor configured to differently process the biosignal received by the first signal connector based on whether power is supplied to the electrode unit; and the electrode unit comprising: at least one active electrode configured to connect with the biosignal processor, wherein the biosignal is sensed through at least one metal electrode being a direct contact type electrode, when the biosignal processor and the electrode unit are not connected such that no power is supplied through the first power connector to the electrode unit, and wherein the biosignal is sensed through the at least one active electrode being a capacitive coupling active electrode, when the biosignal processor and the electrode unit are connected by the first power connector and a respective second power connecter of the electrode unit such that power supplied from the power supplier is provided to the at least one capacitive coupling electrode; and a second signal connector capable of removably attaching to the first signal connector of the biosignal processor, wherein the second signal connector is configured to transfer the biosignal to the biosignal processor. connect with the biosignal processor, wherein the biosignal is sensed through at least one metal electrode being a direct contact type electrode, when the biosignal processor and the electrode unit are not connected such that no power is supplied through the first power connector to the electrode unit, and wherein the biosignal is sensed through the at least one active electrode being a capacitive coupling active electrode, when the biosignal processor and the electrode unit are connected by the first power connector and a respective second power connecter of the electrode unit such that power supplied from the power supplier is provided to the at least one capacitive coupling electrode; and a second signal connector capable of removably attaching to the first signal connector of the biosignal processor, wherein the second signal connector is configured to transfer the biosignal to the biosignal processor.