Abstract: With the enzymatic hydrolysis lignin (EHL) as the raw materials, and the phenol-sulfuric acid method was used to modify EHL. Under alkaline conditions, the lignin-epoxy resin (L-EP) was synthesized by phenolated lignin (PL) reacted with epichlorohydrin (ECH). The structure of EHL and its modification and the synthetic resin were analyzed by FT-IR. The effects of single factor reaction conditions on the process of phenolation were discussed. The results indicate that the effect of modification is the best under the condition of 3.0 h, 95℃ and 4 mL/g H₂SO₄ (2 mol/L), and the content of phenolic hydroxyl group reaches 4.632 mmol/g, which increases by 42% compared with EHL. The effects of different L-EP adding amount on the mechanical properties and thermal properties of L-EP/epoxy E-51 composites were investigated. The results show that the tensile strength of L-EP/epoxy E-51 composites is the best when the amount of L-EP is 5%, which increases by 26% compared with that of the pure E-51 epoxy resin. With the increase in the amount of L-EP, the thermal stability of L-EP/E-51 composites is enhanced. The non-isothermal method was used to analyze the curing kinetics of epoxy E-51 and L-EP/E-51 composites. The results reveal that L-EP has a certain effect on the curing of L-EP/epoxy resin composites.