ULTRASONIC PHYSICAL PROPERTIES MEASUREMENT DEVICE

[Problem] To provide an ultrasonic physical properties measurement device that suppresses the generation of a secondary flow inside a cylinder, is more portable, and can suppress changes in physical properties.[Solution] An ultrasonic physical properties measurement device 1 that: uses ultrasonic waves to measure the flow velocity profile of fluids that flow inside a cylinder 2, by rotating the cylinder 2 backwards and forwards in a fixed cycle; and calculates the physical properties of fluid from the flow velocity profile. The cylinder 2: has an upper end surface 21 and lower end surface 22 that are penetrated such that fluid can flow therethrough; and comprises a rotation mechanism 3 that supports all or part of the cylinder 2 in a state of immersion in the fluid and rotates the cylinder 2 backwards and forwards.