This paper presents the growth conditions and characteristics of polycrystalline (poly) 3C-SiC thin films for applications related to harsh environments. The growth of the poly 3C-SiC thin film on the oxided Si wafer was carried out by (atmospheric pressure chemical vapor deposition) APCVD using hexamethyildisilane (HMDS, Si 2 (CH 3 ) 6 ) precursor. To obtain an optimized growth condition, we have performed depositions under various conditions that temperature adjusted from 1000 to 1200°C, the HMDS flow rate changed from 5 to 9sccm, and carrier gas (Ar) kept up 500sccm. Each sample was analyzed by XRD (X-ray diffraction), XPS (X-ray photoelectron spectroscopy) and GDS (glow discharge spectrometer). SEM (scanning electron microscope) was utilized to determine layer density, voids and dislocations of the cross-section. From the results of experiment, we have obtained that temperature and HMDS flow rates of the optimized polycrystalline 3C-SiC thin films growth condition were 1100°C and 8sccm, respectively.