Abstract: In order to reveal and reasonably utilize the internal relationship between aeration rate and froth entrainment of gangue fines in flotation，a self-made froth overflow rig was adopted to simulate the influencing rule of aeration rate to the properties of froth and entrainment of gangue.Results indicated that：in the two-phase foam，the increase of aeration rate effectively lower the coalescence rate and sauter diameter of bubbles，greatly reduce the foam drainage，and increase the foam fluid rate and apparent fluid rate.Thus，the rate of water recovery can be increased remarkably.In three-phase froth，recovery of gaugues in froth layer is significantly increased when the aeration rate was increased.Thus，controlling the aeration rate is beneficial for reducing the froth entrainment of gangue finess in flotation process under the premise of reasonable concentrate recovery.

Key words: Aeration rate, Froth properties, Froth entrainment