The results have shown that the colloidal and rheological behaviors of KGM in water were significantly affected by pH and temperature. At room or relatively low temperatures, the pH level strongly affected the average molecular weight and particle size of KGM but not the chain conformation. Acidic conditions pro- moted the degradation and disaggregation of molecular chain whereas alkaline conditions favored its aggregation. KGM remained in random coil conformation in all pH conditions. The pH range sig- nificantly affected the rheological behaviors of KGM upon thermal treatment. In relatively acidic conditions, thermal treatment pro- moted the dispersion of KGM or the formation of a stable solution in water. In alkaline conditions, KGM presented the typical gelation process at temperature over 60◦C. These effects of pH and tem- perature on the colloidal and rheological behaviors were mostly attributed to the changes in intermolecular interactions instead of deacetylation.