Systematic pilot experiments were performed under an average temperature gradient of 0.37℃/cm over the thermocline in a stratified reservoir model. The process of inducing internal waves by aeration was analyzed, the types of aeration-induced internal waves were explored, and the effects of disturbing source from aeration and the thickness of the thermocline on the generation and characteristics of internal waves were mainly investigated. The air-water two-phase flow generated from the water-lifting aeration was a kind of unsteady periodic disturbing source, the water in the reservoir model was driven to oscillate up and down by the air-water two-phase flow, and the internal waves were then induced by this oscillation in the stratified fluid. From the point of inducing source, the aeration-induced internal wave can be classified into a kind of wake-generated internal wave. The amplitude of internal waves peaked when the releasing periods of air piston were within the range of 44.06~58.69s. The internal waves were unable to be induced continuously when the releasing periods of air piston were longer than 180s. The amplitudes and periods of internal waves tended to increase with the diameter of the outlet of the water-lifting aerator. The generation of internal waves was also influenced by the thickness of the thermocline. Under constant temperature gradient, the amplitudes and periods of internal waves tended to increase with the thickness of the thermocline.