For the past two decades diverse technological advancement in X-ray crystallography have resulted in faster determination of structures of large macromolecules especially proteins. Although the capacity to produce diffraction-quality crystals suitable for exhaustive structural analysis remains a bottleneck, even with the combined automated technology cum site directed mutagenesis. Research in the crystallization of protein in microgravity promises to proffer solution to some of the grey areas as crystals of better quality are produced in the microgravity compared to the Earth’s environment. This is used extensively in drug development especially monoclonal antibodies (MABs); and in other applications has been acknowledged by some group of scientists and those of the International Space Station (ISS). This paper recapitulates the account of some of the work done by these scientists on protein crystals yielded in microgravity and the application of the crystals in MABs drug development and other important areas.