Abstract: The goal of the research is to improve the corrosion resistance by using coating polymer nanocompsite which prepare from acrylonitrile and manganese chloride and nickel chloride on carbon steel (45) alloy in saline water (3.5% Nacl) at different temperature (293, 303, 313, 323) K. The inhibition efficiency (PE) reaches 89% at 303 K. Several examinations have been conducted for nanocomposite such as (FT-IR) Fourier Transformation Infrared spectroscopy, (XRD) X-rays Diffractions and (AFM) Atomic Forces Microscopy. The outcomes of X-rays and AFM revealed that the nano composite was hybrids of the metal oxides nanoparticle and the polymer that had been uniformly dispersed in general. Spectra of oxide of FTIR appear in the ranges 400-600 cm-1 that reveals the formations of single phases spinal structures that have tetrahedral, octahedral site and two sub lattices. One of the peaks appearing in the ranges of 1100-1130 cm-1 are because of C-O stretching by an hydride groups in the metal oxide, emphasize the acrylonitrile constituted as a polymer with spinal oxides.