The influence of different sources of stress concentration on the plastic deformation of the Zr41.2Ti13.8Cu12.5Ni10Be22.5 metallic glass during room temperature compression tests is evaluated. Stress concentration introduced by sample geometry has a significant effect on the mechanical properties: in contrast to the specimen with square cross-section, which shows negligible plastic deformation, a substantial improvement in the plasticity can be achieved for the sample with round cross-section. Simulations of the stress distribution during the compression tests reveal that the stress concentration at the interface corners is responsible for the early fracture of the sample with square cross-section. Additionally, stress concentration during compression tests in the samples with square cross-section can be significantly reduced, and plastic deformation can be enhanced, by removing the interface corners as well as by reducing the friction arising between loading platens and specimen.