提出了一种用于微量体液密度测量的超声波传感器结构，并对其进行了理论分析和初步实验，结果表明：这种传感器结构与传统的体液密度传感器相比，具有测量精度高、所需试样少、响应快等特点，具有广泛的应用价值。 A structure of ultrasonic sensor for measurement of micro body fluid density was put forward. Theoretical analysis and preliminary experiment were carried out. The results show that compared with the traditional body fluid density sensor, this sensor has the advantages of high measurement accuracy, Like less, fast response and other characteristics, has a wide range of applications.