A device for simulating carbon dioxide storage in a deep saline aquifer, including a CO2 gas source, first and second valves, first and second pressure pumps, first, second and third pressure gauges, a water storage tank, a simulation box, a first flow meter, a gas-liquid separator, a recycling tank, a microcomputer-display assembly, a structure plate, core holders, an injection pipeline, a connection pipeline, a baffle, a piezometer, a second flow meter, a heater, a lifter and an acoustic logging tool. The CO2 gas source, the first valve, the first pressure pump and the first pressure gauge for gas injection. The water storage tank, a second pressure pump and a second pressure gauge for water injection. The second valve, the third pressure gauge, the first flow meter, the gas-liquid separator and the recycling tank form an output pipeline.