RESUMEN
Study on traditional Chinese medicine (TCM) syndrome has been lasted for more than 50 years, which made the syndrome problems become syndrome difficulties. TCM syndrome has become a bottleneck problem and the key scientific problem which restricted the development of TCM theories. The exploration of syndrome difficultiesshowed that syndrome is a unique complex with double structure, which contained the functional structure andsubstantial structure. Uncovering the mathematical sciences connotation inherit in TCM theoretical system, exploring methods of objective and quantitative characterization of the syndrome, deciphering the functional structure of syn-drome, can make a key technical route for TCM theoretical system knowledge innovation in order to reveal the sub-stantial structureof syndrome. It is hopeful to re-open a new era of TCM theoretical innovation and great practice.