Metals are increasingly used in engineering due to their high specific strength. However, some of pure metals do not posses good corrosion resistance. Therefore carbon nanomaterials (CNMs) has been studied to overwhelm the corrosion existed on the metal’s surface. CNMs are synthesized directly on various metal substrates by Chemical Vapor Deposition (CVD) technique without addition of any external catalyst, in reactor at temperature of 800°C. Argon with a flow rate of 200ml/min was used as a carrier gas and acetone as a carbon source. In this study, two different metals were used as metal substrate: mild steel and stainless steel 316. The morphology, existence of CNTs and elemental analysis of the CNMs on metal substrate are evaluated using Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD) and Energy Dispersive X-ray (EDX), respectively. It was proven that the different element composition of metal substrate influenced the size and morphology of CNMs. The most suitable metal to grow CNTs was found to be stainless steel.