Abstract: A method for nondestructively detecting an elasticity of a viscoelastic medium and a device for nondestructively detecting an elasticity of a viscoelastic medium are provided. The method comprises steps of: a) driving an ultrasonic transducer probe with a low-frequency vibration by a vibrator so as to produce an elastic wave to be propagated in the viscoelastic medium, transmitting an ultrasonic wave to the viscoelastic medium by the ultrasonic transducer probe, and collecting an ultrasonic echo returned from the viscoelastic medium; b) selecting an effective ultrasonic echo from the ultrasonic echo according to a duration of the low-frequency vibration and physical parameters of the viscoelastic medium; c) calculating a propagation velocity of the elastic wave in the viscoelastic medium according to the effective ultrasonic echo; and d) calculating the elasticity of the viscoelastic medium according to the propagation velocity of the elastic wave.