Abstract: Shear strengthening is required when an RC beam is found deficient in shear, or when its shear capacity falls below its flexural capacity after flexural strengthening. This study presents a state-of-the-art review of existing research on this topic. The research programs conducted to investigate the shear performance and to evaluate the shear capacity of the strengthened beams are reviewed in this paper by details. The research is a good reference for all engineers and researchers in fields of shear strengthening and repair RC beams in building and bridges.