To investigate sludge organic matter (VS/TS), the related rheological properties, extracellular polymeric substances (EPS), and sludge de-watering performances with respect to analysis and others, samples of six types of surplus activated sludge were taken from the typical bio-fermentation products enterprises in China, including the manufacturers of monosodium glutamate, citric acid, soy sauce, vinegar, lysine and yeast. Findings of the study revealed that VS/TS content of the surplus activated sludge in biological fermentation industry ranged from 62.22% to 82.53%, and the sludge de-watering performances varied quite a little; the sludge de-watering performances of yeast and citric acid production was the worst of all, with the values of capillary suction time (CST) being respectively (259.44±9.87) s and (251.71±8.85) s, and specific resistance of filtration (SRF) being (3.85±0.21)x1014 m/kg and (2.61±0.17)x1014 m/kg, respectively, the next being the sludge from manufacturers of vinegar and monosodium glutamate; the initial viscosity (shear rate 10 s-1) of different sludge changed far greater than infinite viscosity (shear rate 300 s-1), but all the sludges had significant positive correlation with CST and SRF, which indicated the characteristics of sludge from biological fermentation industry featured: the greater the viscosity value, the worse the sludge de-watering performance; and CST, SRF, sludge viscosity and others were however inversely proportional to the organic matter content (VS/TS), that was contrary to the characteristics of the surplus sludge from municipal sewage treatment plants. The analysis of sludge organic matter components in EPS showed that the amount of organic components in all kinds of the sludge (except for lysine sludge) ranked in descending order: protein > polysaccharide > humic acid; the total protein contents of yeast and citric acid sludge were (624.96±24.08) mg/(g TS) and (361.30±3.11) mg/(g TS), respectively, and the total polysaccharide content of lysine sludge was as high as (361.59±11.60) mg/(g TS); the distribution of protein content in EPS layers of the above-mentioned sludge was TB-EPS>Slime-EPS>LB-EPS, and nearly half of the protein and poly-saccharide contents were found in TB-EPS layer. In view of the analysis of three-dimensional excitation-emission matrix (3D-EEM) fluorescence spectroscopy, tryptophan protein, being the main protein substance, accounted for the largest proportion of each EPS. In addition, correlation analysis with de-watering performance showed that humic acid and protein components in sludge were significantly positively correlated with viscosity, CST and SRF; protein had greater impacts on sludge viscosity and de-watering performance than humic acid; and the protein content of Slime-EPS and LB-EPS much more affected sludge de-watering performance. [ABSTRACT FROM AUTHOR]