Carbon nanotubes (CNTs) have been widely used to strengthen different types of materials including polymers, ceramics, and metals due to their extraordinarily high strength. In this work, we investigated the influence of CNTs on the mechanical characteristics of amorphous metallic glasses by using molecular dynamics simulations. We constructed long (continuous) and short (discontinuous) CNT-reinforced metallic glass nanocomposites, determined their stress–strain responses and elastic modulus, and compared their tensile and compressive behaviors with monolithic metallic glasses. It was found that long CNTs dramatically increased the stiffness and yield strength of the metallic glass, and improved their elastic region of deformation and ability to absorb energy. In contrast, metallic glasses reinforced with short CNTs showed almost no improvement of mechanical properties.