Provided is a technique for evaluating properties of a membranous tissue or a surface of the tissue in a biological body by ultrasonic waves. A method of the invention includes setting one or more measurement points on a surface of the biological tissue to be inspected； measuring, in a state in which an elastic wave propagates to the biological tissue, at least a surface wave of the elastic wave by measuring a displacement of the biological tissue at the measurement point by using an ultrasonic wave； and calculating an index value indicating physical properties of the biological tissue by using the measured displacement.
