Lamb wave Dispersion Ultrasound Vibrometry (LDUV) is an ultrasound-based technique for measuring viscoelasticity of soft tissues with plate-like geometry. The technique uses a mechanical actuator or focused ultrasound radiation force to excite Lamb waves in the medium of interest and a pulse echo transducer to track the deformation and estimate phase velocity. Lamb wave dispersion equation is fitted to the measured Lamb wave velocity dispersion (change in phase velocity as a function of frequency) to estimate elasticity and viscosity of the medium. In this comparative study, we report measurements of elasticity and viscosity of excised porcine left-ventricular free wall myocardium, excised porcine spleen and a gelatin plate, obtained using LDUV and Magnetic Resonance Elastography (MRE). The estimated elasticity and viscosity obtained using the two methods agree within one standard deviation for all three samples.