BACKGROUND:Both correspondence analysis and two-step cluster analysis are high-grade statistical analysis, the introduction of these analyses into the research on traditional Chinese medicine (TCM) syndrome type of knee osteoarthritis wil provide objective evidence for the standardization and normalization of TCM syndrome type, through the combination of mathematical statistical principle and TCM syndrome type. OBJECTIVE:To explore distribution characteristics of knee osteoarthritis TCM syndrome type using correspondence analysis and two-step cluster analysis. METHODS:The clinical symptoms of 200 patients with knees osteoarthritis were investigated through a knee osteoarthritis symptoms questionnaire. According to the criteria for three kinds of syndrome type issued in Diagnostic Criteria for TCM Syndrome, the characteristics of each syndrome were analyzed using two-step cluster analysis and corresponding analysis. Then knee osteoarthritis TCM syndrome type characteristics were defined. RESULTS AND CONCLUSION:Cluster analysis is ineffective for the syndrome type, which is not present in the Diagnostic Criteria for TCM Syndrome. Corresponding analysis showed that, in addition to kidney marrow deficiency syndrome (50.5%), yang deficiency and congealing syndrome (13.5%), and blood stasis syndrome (23%), concurrent syndromes were also found, including kidney marrow deficiency combined yang deficiency and congealing syndrome (6.5%), yang deficiency and congealing combined blood stasis syndrome (3%), kidney marrow deficiency combined blood stasis syndrome (3.5%). Therefore we performed corresponding analysis. After analyzing the syndromes at 0.5, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5 radius, the most reasonable syndrome was those at 1.1 radius by corresponding analysis. Corresponding analysis is a scientific method for the classification of knee osteoarthritis syndrome.