Microalgae produce biomass used as one of the renewable energy sources. The utilization of photobioreactor is meant to control some parameters affecting microalgae growth and reduce the possibility of contamination. The optimal photobioreactor is required to obtain the best microalgae growth. This research is proposed by comparing two different photobioreactors (non-baffle and horizontal baffle) to get insights on the optimal configuration so that the mixing and good microalgae growth can be achieved. ANSYS Fluent is used to solve the CFD model. User-defined functions were used to integrate the microalgae kinetic equations into three-dimensional photobioreactor. Microalgae growth simulation results are obtained dependently over space and time within photobioreactor for several days. The simulation results showed that the microalgae growth in photobioreactor with horizontal baffle was better than the non-baffle photobioreactor.