Epoxy resins are widely utilized as high performance thermosetting resins for many industrial applications but unfortunately some are characterized by a relatively low toughness. Laccol (LC) is a natural phenol with two hydroxyl groups in octo-position and long side unsaturated hydrocarbon substitute C17H31. Epoxy-Iaccol (EP-LC) oligomers were synthesized by reaction of epoxy resin Epikote 828 with LC (1:1 eq) at temperature 140 +/- 2 oC for 4 hrs in nitrogen condition. The mixture of EP-LC with Epikote 828 is named Epolac. Using Epolac, the effect of LC content on the mode-I interlaminar fracture toughness (GIC) and mechanical properties of epoxy polymers were evaluated. The obtained testing results showed that the Izod impact strength of glass fabric/epoxy (GF/EP) composites significantly increased by 44.1 percent from 179.05 KJ/m2 to 258.04 KJ/m2, while the mode-I interlaminar fracture toughness for crack initiation and propagation also improved by 29.5 percent and 20.0 percent, respectively, when 20 percent LC was participated in the epoxy matrix. Results obtained from dynamic mechanical thermal analysis (DMT A) showed that the glass transition temperatures of the epoxy resin matrix were slightly reduced on the addition of laccol. The scanning electron microscopy (SEM) observation revealed that LC delayed the crack growth in GF/EP composite as well as the onset of matrix crack. The overall results have shown that it is possible to obtain excellent impact strength and the mode-I interlaminar fracture toughness (GIC) with the use of laccol as a toughness agent for the epoxy resins.