The present invention relates to a device and method for automatically detecting the blood pressure. It mainly includes a blood pressure detection device in contact with a users foot, a computing unit electrically connected to the blood pressure detection device, a transmission unit electrically connected to the computing unit, a receiving unit configured to receive the information transmitted from the transmission unit and electrically connected to a display unit and a parameter input unit electrically connected to the computing unit. When a user intends to measure his/her blood pressure, weight and heartbeat, the user first initiates the blood pressure detecting device and input parameters of the user (e.g., height) through the parameter input unit. By using the blood pressure detection device, the preliminary blood pressure of the user can then be synchronously detected with the resonance wave. The computing unit then integrates the input parameters and the preliminary blood pressure to calculate the correct blood pressure of the user. The transmission unit then transmits the correct blood pressure, weight, or heartbeat to the receiving unit for display on the display unit.
