Bubble is widely used in separation processes to separate useful material from others. The bubble separation process utilizes the hydrophobic and hydrophilic surface properties as encountered in flotation. The bubble characteristic determines the separation process so that research of the phenomenon of bubble production becomes important. One method to generate bubbles is to utilize the phenomenon of water entrainment. This study aims to determine the parameters that influence the bubble production by air entrainment vertical jet impingement in the surface of the water, especially on the effect of jet height on air entrainment rate, bubble depth penetration, and bubble size. Set up experiment consist of pump, nozzle, don comer, water flow meter and water pool. The datas are represented by videos and photos obtained by using camera and video with back lighting. Data in the form of image processed with image processing program to obtain quantitative data. The results showed that jet height affects the water entrainment rate, bubble depth penetration, and bubble size.