Abstract: Stable isotope labeled  L tryptophan is an application of nucleus technology in amino acids. Progresses in stable isotope labeled  L tryptophan in recent years are reviewed. In the respect of synthesis, in addition to the methods of organic synthesis and isotope exchange, the microbial technology which has the advantage of U label and construct has been used widely. In the respect of applications, stable isotope labeled  L tryptophan as trace has been used widely in yields of medicine, biology and chemistry et al. Along with the development of protein engineering, molecular biology and peptide drugs, they will have a fine future