A method for obtaining an elastic feature of an object includes inducing a first shear wave in the object by transmitting a first push ultrasound signal which is generated by a probe of an ultrasound apparatus and a first grating lobe signal which relates to the first push ultrasound signal toward the object, transmitting a tracking ultrasound signal to an area of the object where the first shear wave has propagated, receiving, from the object, a reflection signal which relates to the tracking ultrasound signal, measuring a first shear wave parameter which indicates a shear wave characteristic of the first shear wave based on the reflection signal, and obtaining an elastic feature of the object by using the first shear wave parameter.
