Thermodynamic analysis employing Gibbs free energy minimization for aqueous phase reforming of three model compounds in bio-oils for hydrogen production was presented. Effect of temperature (340～660K) and pressure ratio psys/pH2O(0.1～2.0) on H2 and CH4 selectivity, carbon formation and conversion of model compounds were calculated. The results showed that when considering both methanation and carbon formation reactions, the conversion of the model compounds were over 9999% and no carbon formation was found, but mathanation was far more thermodynamically favorable than hydrogen production reaction. H2 selectivity were greatly improved without mathanation. Further analysis showed that the H2 production mechanism was mainly related to directly cracking of model compounds other than to aqueous reforming reaction, however, it was found that about 0.999, 1.940, 1.999 mole solid carbon formed when feeding per mole of methanol, acetic acid and ethylene glycol in the inlet streams. After restricting both mathanation and carbon formation reaction in the system, aqueous phase reforming of methanol, acetic acid and ethylene glycol at temperature of 500K and psys/pH2O of 1.1 could achieve H2 selectivity of 74.98%, 66.64%, 71.38%, and the conversion of the feedstocks were over 99%.