Abstract: In response to the complex internal flow process and low efficiency of liquid gas jet pumps, this paper uses Fluent software to analyze the variation law of the internal flow field of liquid gas jet pumps. The influence of different throat diameter ratios, nozzle positions, and nozzle structures on the jet performance of liquid gas jet pumps was simulated and studied. The results show that the ratio of the throat diameter of the jet pump to the nozzle outlet diameter directly affects the jet performance of the jet pump, and there is an optimal throat diameter ratio. When the throat diameter ratio is 2, the injection coefficient of the jet pump is maximized. When the distance between the nozzle of the jet pump and the inlet of the mixing chamber is different, the injection performance of the jet pump is also different. When the nozzle distance is 70 mm, the injection coefficient of the jet pump is the highest. When different nozzle structures are used, the cosine nozzle has the best injection performance, while the cylindrical nozzle has the worst injection performance.