To provide a fuel gas purification apparatus that can purify a fuel gas originating from a biomass into high-purity one and to provide a power generation system and a fuel synthesis system comprising the fuel gas purification system.

The fuel gas purification apparatus is provided with a gas purification container 11 for introducing thereinto a pyrolyzed gas generated by pyrolysis of a biomass, a porous body 12 disposed in the gas purification container 11 so that the pyrolyzed gas passes therethrough, a carbonate salt-supplying means 13 for supplying a melted carbonate salt 17 to the porous body 12 to make the porous body 12 hold the melted carbonate salt 17, where the gas purification container 11 is constituted so that it discharges to the outside a fuel gas obtained by purification of the pyrolyzed gas passing through the porous body 12 by a reaction with the melted carbonate salt 17.