A novel self-curing epoxy resin was synthesized using bio-oil. Bio-oil was produced by hydrothermal liquefaction of loblolly pine and utilized as a biopolyol in the synthesis of bio-oil-based epoxy resin (BOBER) for the first time: Hydroxyl groups in bio-oil were analyzed by quantitative P-31 NMR. It was found:: that not only does the total hydroxyl number of bio-oil influence the yield and epoxy equivalent weight of BOBER, but also the distribution of hydroxyl groups within bio-oil (aliphatic, phenolic, and acidic OH) played an important role in the determination of the optimum amount of catalyst in the synthesis of BOBER. Differential scanning calbrimetry analysis proved the self-curing phenomena of BOBER, and Fourier transform infrared spectroscopy suggested that etherification reaction was the dominate reaction during the self-curing. Glass transition temperature cross-linking density and the storage modulus of self cured BOBER were calculated using a dynamic mechanical analyzer.