In vivo, non-invasive measurements of the stiffness (elastic modulus) of biological tissue can be performed with magnetic resonance elastography (MRE). Many studies have illustrated the versatility of MRE; stiffness estimates have been obtained from liver, muscle, breast, brain and heart. Tissue health or disease is often indicated by its stiffness. In many cases tissue health is determined through invasive biopsy, which can subject the patient to discomfort and various risks. Non-invasive procedures, such as palpation, are qualitative, suffer from patient-to-patient variability, and are impossible in deep tissue. Furthermore, these measurements often only provide results in localized regions. However, with the continued development of MRE equipment and protocols, regional non-invasive measures of stiffness are becoming feasible in most soft tissues. In this study we demonstrate the measurement of loss and storage modulus of vitreous humor of the mouse eye using MR elastography non-invasively, in vivo.