Myocardial stiffness plays an important role in cardiac function. The objective of this study is to evaluate if 3D high frequency cardiac MR elastography (MRE) can measure increased myocardial stiffness in cardiac amyloidosis patients compared to healthy volunteers. Twenty-two patients with cardiac amyloidosis and 16 healthy volunteers were enrolled. The myocardial stiffness of cardiac amyloid patients (median: 11.4 kPa, min: 9.2, max: 15.7) was found to be significantly stiffer (p < 0.01) than healthy controls (median: 8.2 kPa, min: 7.2, max: 11.8). These results motivate future investigation of 3D high frequency cardiac MRE in different patient cohorts.