Provided herein is a phantom capable of mimicking both a dense breast and a fatty breast. A phantom for ultrasound measurement includes: a first member that mimics an object of interest for measurement and a second member having provided therein the first member. The second member has the property to decrease its sound speed with a temperature increase brought by external temperature control. The sound speed of the second member at a predetermined temperature is equal to the sound speed of a third member surrounding the second member. The first member and the second member are immiscible with each other.
