OBJECTIVE To explore the correlation between syndrome differentiation and CT quantitative diagnosis of fatty liver. METHODS One hundred and thirteen cases of fatty liver verified clinically accepted plain CT scan after syndrome differentiation (syndrome of stagnation of liver qi and spleen deficiency, syndrome of intermingled phlegm and blood stasis, syndrome of phlegm-dampness blocking internally, syndrome of deficiency of liver and kidney, syndrome of interior dampness-heat), and then the CT values of the liver and the spleen were measured respectively. RESULTS It was shown that there was a correlation between the syndrome differentiation and the fatty infiltration in the liver. Significant differences of the distribution of fat and the ratio of liver-spleen were found among the five different syndromes (P<0.05). Diffused, mild fatty liver mainly displayed syndrome of stagnation of liver qi and spleen deficiency. CONCLUSION Syndrome differentiation of fatty liver is correlated with CT quantitative diagnosis, which can be discriminated by the ratio of liver-spleen.