Simultaneously conductive and very tough thermoset formulations are desired for applications such as lightning strike protection or electrostatic dissipation for aerospace industry. Within the scope of this research, diglycidylether of bisphenol A (DGEBA) cured with 4,4’-diaminodiphenyl sulfone (4,4’-DDS) is chosen as the reference epoxy system and modified with an industrially available, electrically conducting carbon black in combination with various types of tougheners to simultaneously increase the resistance to the fatigue crack growth and electrical conductivity. As toughening agents core-shell particles and two different grades of functionalized tri-block copolymer of PMMA-b-PBA-b-PMMA were used up to 10 wt%. Electrical conductivity of above described multifunctional nanocomposites are characterized with 2 point conductivity measurements. In addition, the effect of the tougheners morphology on the electrically conductive network formation of the carbon black and as well the fatigue crack growth resistance is studied systematically. Addition of carbon black and various tougheners did not affect the Tg of the DGEBA-4,4’-DDS. The addition of all tougheners increased the fatigue crack growth resistance (da/dN) of the neat system. Especially heterogeneously distributed core shell and M52N increased the resistance to initiation of crack propagation and as well the critical failure. Tougheners with the homogeneous dispersion and heterogeneous distribution promoted the conductive network formation of carbon black even further and increased the electrical conductivity almost 100 times compared to the nanocomposites of only carbon black. On the other hand, nano-phase separated toughener with homogeneous dispersion and distribution having averagely 30 nm soft-phases hindered very strongly the conductive network formation of carbon black.