Many materials produced by smoking cigarettes such as nicotine and tar are harmful to human health. Whilst here has been much research in the tobacco industry to reduce the risks of smoking it has not been reported that Fe-carbon can reduce the tar in the main-stream smoke of cigarettes. In this paper, it is shown that adding 5% by weight of coconut carbon to reconstituted tobacco in cigarettes can reduce cigarette tar by 9.73%. Based on the researches of coconut carbon, another additive, Fe-coconut carbon reconstituted tobacco was prepared and it can reduce 16.76% of cigarette tar without changing the cigarette taste. The effects of Fe-coconut carbon reconstituted tobacco on reducing cigarette tar depend on conditions such as pH value. For example, the Fe-coconut carbon prepared at pH=12 has a better effect than the Fe-coconut carbon prepared at pH=5. The results of XRD analysis and TG analysis indicate that the hydroxides of Fe prepared at different pH values are different. The hydroxide of Fe prepared at pH=12 is more easily transformed to -Fe₂O₃ than the hydroxide of Fe at pH=5. The newly formed α-Fe₂O₃ can promote the burning of cigarette tobacco and reduce the cigarette tar.