Low energy ion irradiation is an interesting tool to accomplish the bulk modifications of different materials. The impact of low energy ion bombardment is studied on Cu-C(70 )nanocomposite thin films prepared by thermal co-deposition technique. A beam of 180 keV Ar ions was used for this purpose which results in a drastic change in structural, optical and electrical properties. It is demonstrated that surface plasmon resonance (SPR) was successfully induced with ion irradiation initially at a fluence of 3 x 10(14) ions cm(-2) and is observed to be first red shifted and then blue shifted on increasing fluence of ion irradiation. The results of Raman spectroscopy reveal the progressive transformation of fullerene Cm into amorphous carbon with increasing fluence. The I(D)/I(G) ratio is calculated to analyze amorphous carbon and improved ordering of amorphous carbon at higher fluences is observed. TEM images verified the continuous growth of copper nanoparticles subjected to low energy ion irradiation with increasing fluence which is ascribed to the agglomeration of particles as pointed by EDS mapping images. FTIR results show that the destruction of fullerene C-70 matrix is initiated at a fluence of 3 x 10(14) ions cm(-2 ), which coincides with the appearance of SPR band. The transformation of fullerene into amorphous carbon and the growth of copper nanoparticles was found to be responsible for increase in conductivity with fluences as confirmed by I-V measurements.