The current work is based on the simulation modeling of steam gasification of palm kernel shell (PKS) with CO2 capture through sorbent (CaO) using Aspen plus. The simulation model is developed using a Gibbs free energy minimization method. The objective of this work is to investigate the effect of key parameters like temperature, steam/biomass ratio, and CaO/biomass ratio on syngas yield. The system performance was also evaluated through carbon conversion efficiency, cold gas efficiency and gasification efficiency, lower and higher heating values by varying the gasification temperature, steam/biomass ratio, and CaO/biomass ratio. The H-2 concentration increased from 65 to 79.32 vol % with the increase of temperature from 650 to 700 degrees C. The CO2 content was reduced from 20 to 5.32 vol % by increase in CaO/biomass ratio from 0.5 to 1.42. The maximum hydrogen content predicted is 79.32 vol %, and the minimum CO2 content is 5.42 vol % found at operating parameters including a temperature of 700 degrees C, steam/biomass ratio of 1.5, and CaO/biomass ratio of 1.42. In addition the simulation model predicted results were compared with experimental data obtained from the experimental set up used in the simulation.