An all polymeric electrically conductive thermoset adhesive resin system is prepared for future lightning strike protection applications. Polyaniline (PANI)-based hybrid nano-composite is prepared by incorporating high apparent-density type vapor grown carbon fiber (VGCF-H) as additional conductive filler. Electrical, mechanical and electromagnetic interference (EMI) shielding properties of PANI-dodecylbenzene sulfonic acid (DBSA), and divinylbenzene (DVB) system are improved with addition of VGCF-H. Different weight percentages of VGCF-H in the PANI-DBSA/DVB matrix, are studied, and their effect on composite's properties are investigated. Electrical conductivity up to 1.89 S/cm with the addition of 5 wt% VGCF-H is achieved, which is almost 300% improvement compared with previous system. However, the maximum flexural modulus is obtained at 3 wt% of VGCF-H. The change in the electronic structure of PANI with the addition of VGCF-H is investigated using Fourier transform infrared (FT-IR) analysis. Rheological study and Differential scanning calorimetry analysis were employed to show the effect of VGCF-H concentration on curing profile of the nanocomposites. EMI shielding properties of the composite with and without VGCF-H are measured in X-band frequencies and compared. Composite with 5 wt% VGCF-H has shown EMI shielding effectiveness about 51 dB in X-band, which is higher than the composite without VGCF-H (around 22 dB). POLYM. ENG. SCI., 59:956-963, 2019. (c) 2018 Society of Plastics Engineers