Gasification technology is recognized as next generation power plant technology which can replace conventional fossil fuel power plant. It produces not only electricity but also chemical energy as a form of syngas. The syngas can be further transformed into valuable chemicals such as H2, DME and liquid fuel etc. It is focused on hydrogen and power (Co-gen) gained by gasification system which is based on 300MWth scale gasification plant with various feedstocks such as Illinois#6 coal, heavy residue oil (bunker-C, naphtha) and bitumen of oil sand in this study. Besides it is considered gasification system with options of CO2 capture technology. The simulation model of the gasification plant is composed of sub-process such as fuel preparing, gasification, ash removal, acid gas removal (AGR) and H2 production process model based on ASPEN plus. Then adding CO2 capture models to the base model of gasification system, its models are compared with their performance of the systems. To research performance of these models, evaluating parameters are chosen as cold gas efficiency and carbon conversion of gasifier, carbon dioxide capture efficiency and production rate of H2 and plant net efficiency.