Abstract: Flocculation of montmorillonite colloids is influenced by the concentration and type of cations in water. NaCl, KCl, CaCl2 and MgCl2 solution were arranged into the same concentration gradient. The deposition process of montmorillonite in solution was observed. It was found that the flocculation of montmorillonite increased with the increase of the concentration of sodium and potassium ions. Calcium and magnesium ions have a critical flocculation value for montmorillonite flocculation, which is more stable than the critical concentration. It is known by the Zeta potential that it is caused by exclusive action.The law below the critical concentration is the same as that of monovalent cations. The ionic type also has an effect on the volume expansion of Montmorillonite. In the same concentration gradient, volume expansion increment ranked NaCl KCl MgCl2 CaCl2. Zeta test results show that the potential causes of flocculation and concentration of liquid suspension is cation valence state that the Montmorillonite Granules electric double layer changes.