Both no-choice and choice bioassays using five different doses of m-tyrosine (aromatic amino-acid analogue; synonym: DL-m-tyrosine) was conducted to determine the feeding response and survival of Formosan subterranean termites, Coptotermes formosanus Shiraki in the laboratory. In no-choice tests, though all the doses of m-tyrosine reduced filter paper consumption, only the highest dose tested (0.05M) was significantly different from the water treated control. This dose also had a significantly high mortality on the termites. In 5-choice bioassays, all the doses of m-tyrosine tested reduced filter paper consumption significantly as compared to control. No significant mortality was observed in the choice tests since very little feeding of filter paper treated with m-tyrosine occurred. From these experiments we conclude that m-tyrosine is toxic to Formosan subterranean termites and acts as a feeding deterrent, therefore, can be a promising ‘nature-based’ wood preservative.