Addition of doping materials can possibly enhance the ionic conduction of solid polymer electrolyte (SPE). In this work, a new SPE using 2-hydroxyethyl cellulose (2-HEC) incorporated with different ammonium nitrate (NH4NO3) composition was prepared via solution casting method. Studies of structural proper ties were conducted to correlate the ionic conductivity of 2-HEC NH4NO3 SPE using X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. Encouraging result was obtained as the ionic conductivity increased about two orders of magnitude upon addition of 12 wt% of NH4NO3. XRD anal ysis shows the most amorphous SPE was obtained at 12-NH4NO3. From FTIR spectra, the interactions between 2-HEC and NH4NO3 were observed by the shifts of C O H peak from 1355 cm−1 to 1330 cm−1 and the presence of new N H peak in the O H region. The spectrum has been validated theoretically using Gaussian software. The results obtained from this study corroborate that the complexes of 2-HEC and NH4NO3 responsible to promote the ionic conductivity to the higher value.