Many preparations of carbon nanotubes have been developed in the last decade, such as arc discharge, plasma-enhanced chemical vapor deposition, simple thermal chemical vapor deposition by pyrolysis of ethyl alcohol, etc. Here we present a simple growth technique of carbon nanotubes by combustion of ethyl alcohol. Pt filament can be employed as substrate, ethyl alcohol as carbon source, and iron nitrate as catalyst precursor. We have characterized the morphology of carbon nanotubes at the different synthesis conditions by both SEM and TEM. In our experiment, we also use other metal as substrate, such as Cu, top of pin, and other catalyst precursor of different concentration, such as nickel nitrate. This technique has some advantages, such as low cost, large production, and flexible reaction conditions, etc. We can use this technique to synthesize carbon nanotubes on metal substrate directly. So this technique has protential applications for fabricating nano-electrical devices.