Introduction: Magnetic resonance elastography (MRE) is a non-invasive technique to quantitatively assess the mechanical properties of biological tissue. Among multiple actuation methods, pneumatic driver is popularly used due to the advantage of good MR compatibility. In this study we set up a prototype pneumatic driver and investigate its performance under MRE with stimulations of various amplitude-frequency pairs.Materials and Methods: Load-free performance of the driver was tested using ultrasound with stimulations of various amplitude-frequency pairs. Performance with load was tested using MRE with both tissue mimicking phantoms and leg muscle. Results: Frequency and amplitude of the external stimulation, mechanical properties of biological tissue, and the length and the diameter of the transmission tube were all found to affect the elastogram reconstruction. Conclusions: A MR compatible actuating driver generating reliable mechanical stimulation is required to guarantee stable propagating shear waves in tissue. Optimal actuating parameters should be properly determined in the practice of MRE for specific tissue.