Study on the coral reef canopy hydrodynamics not only provides guidance for the health of coral reef ecosystem and the ecological restoration project, but also supports the decision-making process for the reef coast hazard prevention and mitigation under extreme wave events such as the typhoons. Meanwhile, it also has significant value for predicting the sediment transport over the reef and the reef coast evolution. This paper reviews the state-of-the-art research on reef canopy hydrodynamics, and systematically summarize the research progress from three aspects: the flows inside and outside of reef canopy, the characteristics of canopy resistance as well as the simulation of canopy resistance. This paper finally proposes the further research directions as follows: future study can focus on the hydrodynamics under more severe wave condition or under combined action of wave and current. It should also fully consider the anisotropy of canopy skeleton. Moreover, it can solve the Navier-Stokes equations directly to reproduce the finer flow field at the canopy scale.