Fixed bed reactor is widely used in the petrochemical industry. The most rigorous description of it is particle-resolved simulation. In this study, a particle-resolved CFD model coupling reaction-diffusion was developed. The gas and porous particle phase were solved separately and the data of heat and mass is exchanged across the phase interface. Detailed flow and reaction process for synthesis of vinyl acetate were investigated by this model. The results showed that the local flow was not uniform under different flow patterns, which leads to the non-uniform distributions of temperature and concentration. In addition, the intra-particle pore diffusion influenced the reactor performance. The increase of particle pore size can obviously promote average reaction rate and decrease product concentration inside particles. The proposed modeling provided deep insight for local flow and reaction-diffusion process and can be extended to entire fixed bed reactor. (C) 2019 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.