NOx and SOx, which are major pollutants of ships, are continuously regulated because they cause soil and water pollution. A scrubber is a typical SOx reduction device and being studied many ways. In this study, the guide vane was installed in the scrubber to improve the scrubber efficiency, and the influence of the swirl flow generated by guide angle on the exhaust gas reduction was analyzed through a computerized analysis. The pressure distribution, velocity distribution, exhaust gas flow, and cleaning water distribution tendency were analyzed when the guide angle was increased from 0° to 75°. The exhaust pressure increased greatly after 60°. The exhaust gas movement distance was maximum at 45 ° and the cleaning water distribution was also distributed most widely at 45°. As the result of the analysis, it was confirmed that the guide angle 45° was most suitable in terms of swirl flow, gas movement distance contacting with cleaning water, cleaning water distribution and exhaust pressure drop. Based on the results of the analysis, a scrubber for a 3300cc commercial diesel engine was installed and tested. The experiment is conducted under the following conditions. Experimental conditions are guide angles of 0 °, 30 °, 45 °, 60 °, 75° and packing rates of 0%, 100% and engine speeds of 700RPM, 1000RPM, 1300RPM, 1600RPM and engine loads of Idle 25%, 50%, 75%, 100%. Fuel consumption time, exhaust temperature, back pressure, NOx reduction rate and smoke reduction rate are measured and compared with the computational analysis results. The results show that the optimized angle of the scrubber guide vane is about 45 °.