Abstract: A device and a method for rapid detection of blood viscosity based on an ultrasonic guided wave of a micro-fine metal tube are provided. The device comprises a blood sampling unit and a blood sampling electrical circuit that are electrically connected with each other and a device shell; the sample feeding tube and the sample discharging tube are respectively arranged at two sides of the device shell, the inlet of the sampling tube is communicated with the outside of the device shell, the outlet of the sampling tube is communicated with the inlet of the blood micro-flow pump through the micro-fine metal tube, the outlet of the blood micro-flow pump is communicated with the inlet of the sample discharging tube, and the outlet of the sample discharging tube is communicated with the outside of the device shell; the magnetostrictive component is arranged outside the micro-fine metal tube.