A negative pressure regulating device for a prosthetic sleeve is provided. The negative pressure regulating device includes a signal processing unit which is electrically connected with a motion detection unit, an air pressure detection unit, a data transmission unit, and a power management unit. The motion detection unit can transmit information according to current actions of a user to the signal processing unit for determining corresponding actions to obtain a predetermined value of negative pressure. A target value set by the data transmission unit can be transmitted to the signal processing unit to overwrite the predetermined value. The air pressure detection unit can input the negative pressure flow of the prosthetic sleeve by connecting with a three-way air pipe joint to determine the negative pressure in conjunction with the signal processing unit. The negative pressure regulating device includes further includes an air intake unit which has a switch and is electrically connected to the signal processing unit. When the negative pressure is higher than the predetermined value, the air intake unit is opened to introduce air so as to reduce the negative pressure to the predetermined value； and when the negative pressure is lower than the predetermined value, the air intake unit is closed and stops introducing air, and the negative pressure is raised to the predetermined value only by an active negative pressure suction device. When the motion detection unit determines that it is in a static posture, the air intake unit is opened to introduce air, such that the negative pressure is decreased, and the user can adjust at any time to the most comfortable prosthetic wearing state. In addition, when there is no power to drive the management unit, the active negative-pressure suction device can perform the negative pressure operation of the prosthetic sleeve, allowing the negative pressure to remain normal.一種義肢套筒之負壓調節裝置，該負壓調節裝置具有一訊號處理單元，且電連接有動作偵測單元、氣壓偵測單元、資料傳輸單元、電力管理單
