<p>In the present study, the ternary nanocomposites of polypyrrole/molybdenum disulfide/reduced graphene oxide (PPy/MoS₂/rGO) have been synthesized using oxidative polymerization techniques with different loading concentrations (5, 10, 15 and 20 wt%) of MoS₂/rGO in polypyrrole (PPy) matrix. The synthesised nanocomposite samples have been employed for EMI shielding in the Ku-band of microwave region which operates between 12.4 and 18&#xa0;GHz. The surface morphology, phase structure and the chemical structure have been studied through scanning electron microscopy (SEM), X-ray diffraction (XRD) and Raman spectroscopy, respectively. A three-dimensional flower-like structure of MoS₂ nanoparticles and a porous structure with uniformly distributed MoS₂/rGO nanocomposites in PPy matrix have been confirmed through SEM analysis. The room temperature dc electrical conductivity, studied through four in-line point-probe method, has been observed to be raised from 0.35&#xa0;S/cm for pristine PPy to 40.40&#xa0;S/cm for the PPy/MoS₂/rGO (PMG) nanocomposite containing 20 wt% of MoS₂/rGO. The maximum value of the total shielding effectiveness (SE_T) has been found to be ~ 40 dB for the sample with 20 wt% concentration of MoS₂/rGO. Furthermore, the relative value of SE_A to SE_R at 15&#xa0;GHz is found to be 74.5% in pristine PPy which increases continuously with increase of MoS₂/rGO concentration and is ~ 83.23% for the PMG nanocomposites with 20 wt% of MoS₂/rGO in PPy indicates absorption dominated shielding effectiveness which makes them suitable over metal based EMI shields. The mechanism of absorption dominated SE_T has also been discussed in detail. The obtained results in the present study have been compared with the earlier available reports. The present study signifies that the prepared nanocomposites are the lightweight, effective and potential EMI shielding materials to safeguard electronic equipments and devices against electromagnetic interference.</p>