To describe the key systems used for Traditional Chinese Medicine (TCM) classification.The TCM classifications used in the International Classification of Diseases-9 Clinical Modification (ICD-9-CM) volume 3, the ICD-10 Procedure Coding System, the International Classification of Health Interventions, and the Medical Subject Headings (MeSH) and Chinese Traditional Medicine and Materia Medica Subject Headings (TCMeSH) thesauruses were compared regarding descriptive terms, structure, and features of TCM interventions.The National Library of Medicine's MeSH thesaurus is ubiquitous. The ICD-9-CM (volume 3), ICD-10 Procedure Coding System, and International Classification of Health Interventions cover insufficient concepts of TCM, and cannot be used directly as classification systems for TCM interventions. In contrast, the TCM contents of the TCMeSH thesaurus are complete, systematic, and detailed, and its hierarchical structure can be used for effective TCM classification.TCM classification is very limited and flawed. The MeSH thesaurus helps decrease the detrimental effect of the language barrier. Similarly, the TCMeSH thesaurus can help those without full command of the Mandarin language to access Chinese literature, but the value of searches using TCMeSH could be improved by collaborative working with Information Specialists who are fluent in Mandarin and understand TCM.