Hydrolysis is a key process in the biorefining of biomass into chemicals and materials necessary for a sustainable and circular economy. Currently, significant technical and economic challenges exist, limiting its commercial viability. However, process improvement and scale-up can be costly and time-consuming due to non-Newtonian rheology and high solid loading of biomass slurries, which change over time as the hydrolysis reaction progresses, leading to complex mixing and mass/heat transfer behaviors. Computation Fluid Dynamics (CFD) has the potential to be a powerful tool for improving biomass hydrolysis. By utilizing experimental rheological data, a digital twin of the biomass slurry-reactor system could be simulated, thereby allowing for the impact of varying different reactor designs and operational parameters to be assessed at reduced time and costs. The number of studies utilizing CFD for biomass hydrolysis modeling has been rapidly growing in the past decade. Although many still utilize single-phase steady-state simulations, more recent studies have applied increasingly complex models, including transient and multiphase conditions, even enzyme kinetic model coupling. Elucidation of the impact from reactor design, geometry, and operational parameters on key process success factors such as mixing homogeneity, power consumption, and productivity has been greatly enhanced by CFD. Nevertheless, this area of study is still in a nascent stage, with potential for future work to improve upon feedstock variety, model complexity, studied parameters, and the use of extracted results. Further development of biomass hydrolysis CFD will enable better commercialization of future biorefining and industrial biotechnological endeavors.