Experiment on effect of raw syngas conditioning with molten salts was carried out in fix bed reactor.The effects of temperature,flux,bubble diameter,molten salts static liquid heights,and inlet gas composition on the composition of product gas and physical properties of molten salts were investigated.In the temperature range of 350℃~500℃,under all experiment cases,CO2 was effectively absorbed by molten salts and CO2 in the syngas was around 2%.Temperature,flux,molten salts static liquid heights had significant effects on composition of H2 and CO in product gas.Molten slats raw syngas conditioning could be a suitable follow-up procedure for gasification or pyrolysis biomass to upgrade syngas quality.