An aortic artery measuring probe, device and a method of measuring the diameter of the aortic artery are provided. The aortic artery measuring device includes the aortic artery measuring probe and a signal processing module electrically connected to the aortic artery measuring probe. The aortic artery measuring probe includes a flexible substrate and a sensor array disposed thereon, wherein the sensor array includes M×N ultra-wideband sensors. The ultra-wideband sensors is positioned on a subject and the flexible substrate is deformed to a profile conforming to the profile of the subject. The ultra-wideband sensors transmit a radio wave into the subject and then the radio wave is reflected by a tissue interface of the artery wall of the aortic artery to form a reflected signal. The ultra-wideband sensors receive the reflected signal and the signal processing module analyzes the reflected signal to define the diameter of the aortic artery.