NO2 in cigarette main smoke of different kind brands was measured continuously by differential optical absorption spectroscopy (DOAS). By using RM200 rotating disk smoking machine with 20 smoking flue, 20 cigarettes were inserted into the rotating disk and ignited every 3 s. By use of DOAS technique, the measurement was completed within 6～7 min after the smoke was transported into a White cell with 31.5 m path length which was connected to the smoking machine. This technique can improve the measuremental temporal resolution compared with traditional method. At the beginning, the press in White cell was 5.2×104 Pa and it increased to 1.03×105 Pa while the measurement finished. The result shows the concentration of NO2 in main smoke is between 0.89 mg/m3 and 1.54 mg/m3 and the concentration of NO2 in main smoke is quite different for different brands cigarette. The NO2 concentration of mixing type cigarette is 83% high than that of roast type cigarette. This technique provides a simple and quick method for analyzing components of cigarette smoke.