One of the gasifiers used in the gasification process is the fluidized bed reactor. Determining the optimal process parameters for a fluidized bed reactor through direct experimentation is both time-consuming and costly. These challenges can be addressed through a computational fluid dynamics (CFD) based numerical approach. In this study, the Eulerian-Eulerian two-phase model coupled with kinetic model will be employed to predict the amount of product produced by chemical reaction. To achieve the best performance of the fluidized bed reactor and optimize the production of syngas, variations in temperature, airflow rate, biomass flow rate, and biomass humidity will be explored to determine the optimal operational conditions for syngas production and selectivity. The simulation results indicate that high-intensity reactions occur around the biomass feed, increasing the temperature in that region. Changes in process parameters influence syngas yield. H2 yield enhanced 3% at 12 L/min air flow rate. Conversely H2 production decreased at inlet air temperature 823 K due to consumed to produce CH4. A high biomass feed rate extends retention time, thereby increasing the likelihood of secondary reactions that produce CO and CH4. Additionally, high water content in the gasification process decreases CO production and increases CO2 production. © 2025 Penerbit UTM Press. All rights reserved.