Current study focuses on the process development of hydrogen production via gasification of Empty fruit bunch (EFB) with in-situ adsorption of C02 based on equilibrium modeling approach. The process flowsheet simulation is performed using iCON, PETRONAS process simulation software. This work investigates the influence of the temperature within the range of 600 to 1000°C and steam/biomass ratio between 0.1 to 1.0 on the hydrogen yield and product gas composition. The importance of different reactions involved in the system is also discussed. Using the simulation, the optimal operating conditions are predicted to be at 800°C and steam/biomass ratio of 0.6. Hydrogen yield of 149g kg-1 of EFB can be obtained at 1000°C. The preliminary economic potential per annum of the oxygen-steam gasification system coupled with in situ C02 adsorption is RM 6.64�l06 or approximately USD 2�l06. © 2011 Asian Network for Scientific Information.