tIn this study, kinetics of the curing reaction between DGEBA epoxy resin and tryptophan as an environ-mentally friendly curing agent in the presence of 2,4,5-triphenylimidazole was reported. The role of silicananoparticles (SiNP) in changing the mechanism of the curing reaction was also studied. The optimummolar ratio of DGEBA/tryptophan and the optimum content of SiNP were determined by calorimetryanalyses. Kinetic analysis using the advanced isoconversional method revealed that the system under-goes the vitrification. Thermogravimetric analysis demonstrated that addition of SiNP does not improvethe thermal stability of the tryptophan based thermosets. Impedance spectroscopy and also the standardfour-probe method were performed to investigate the effect of curing agent and SiNP loading level onthe electrical properties of the cured epoxy. The structure and morphology of the nanocomposite werestudied by X-ray diffraction analysis, atomic force microscopy and scanning electron microscopy imag-ing. Dynamic mechanical thermal analysis revealed that the crosslinking density cannot be significantlyaffected with the addition of SiNP.