Conductive nanocomposites using ethylene acrylic elastomer (AEM) and multiwalled carbon nanotube (MWNT) have been prepared using Haake rheocord. Prior to mixing the MWNT are dispersed in athanol in presence of ionic liquids such as 1-Methyl-3-octylimidazolium chloride (MOIC) and 1-Allyl-3-methyl imidazolium chloride (AMIC). The ratio of the MWNTs with ethanol is 1:30 by weight. In presence of ionic liquid uniform dispersion of MWNT in ethanol as well as in AEM matrix has been observed from the transmission electron microscopic (TEM) photomicrographs. The tensile strength increases up to 6 phr of MWNT loading above this loading the tensile strength decreases. However, the tensile strength marginally increases in presence of ionic liquids and particularly in presence of MOIC ionic liquid the nanocomposites exhibit highest tensile strength. It is observed from the dynamic mechanical analysis (DMA) that the storage modulus (E) and glass transition temperature (Tg) of AEM matrix increase by incorporation of MWNT. The E also increases and the tan Delta max marginally decreases in presence of ionic liquids. The dielectric relaxation characteristics of AEM/MWNT nanocomposites such as dielectric permittivity (E) and AC conductivity (Neu ac) have been studied in the frequency range of 10 raiseto 1 to 10 raiseto 6 Hz at different MWNT loading.The electromagnetic interference shielding effectiveness of the AEM/MWNT nanocomposites (EMISE) is studied in the X-band frequency region (8-12 GHz), which is significantly improved with increase in MWNT loading.