A blood vessel analysis device includes a photoelectric detector, a processor and an ultrasonic detector. The photoelectric detector detects a blood vessel and generates a detecting signal. The processor is connected to the photoelectric detector for receiving the detecting signal. The processor converts the detecting signal into a blood flow information specifying a blood flow condition of the blood vessel, and outputs a driving signal when the specified blood flow condition matches a reference blood flow condition. The ultrasonic detector is connected to the processor. The ultrasonic detector detects the blood vessel and generates a blood vessel diameter information upon reception of the driving signal. Based on this, the detection efficiency is improved. An operating method of the blood vessel analysis device is also provided.
