Objective: To develop a method for determination of aniline,N-methylaniline and N,N-dimethylaniline in air by HPLC.Methods:The separation was carried out on a universal C18 column,methanol was used respectively as mobile phases in analyzing N-methylaniline.The flow rate was 0.7 ml/min,the detector was UV detector.The detective wavelength was set at 243 nm.Results:The linearity of aniline was obtained over the range of 0.00～1000 μg/ml.The regression equation was y=0.000936x+0.53,the correlation coefficient was 0.9998.The limit of detection(LOD) was 0.9 μg/ml,The limit of detection in air was 0.20 mg/m3.The average recovery was 99.2%,100.5%,and 104.4%(with RSD% 0.23%,0.42%,and 3.25%) when the sample concentration was 250,25,and 2.5 μg/ml.The linearity of N-methylaniline was obtained over the range of 0.00～1000 μg/ml.The regression equation Was y=0.00124x+0.02,the correlation coefficient was 0.9999.The limit of detection(LOD) was 0.4 μg/ml.The limit of detection in air was 0.09 mg/m3.The average recovery was 99.7%,101.6%,and 102.0%(with RSD% 0.27%,0.23%,and 3.65%) when the sample concentration was 250,25,and 2.5 μg/ml.The linearity of N,N-dimethylaniline was obtained over the range of 0.00～1000 μg/ml.The regression equation Was y=0.001442x+0.49,the correlation coefficient was 0.9999.The limit of detection(LOD) was 1.0 μg/ml.The limit of detection in air was 0.22 mg/m3.The average recovery was 99.1%,103.5%,and 106.8%(with RSD% 0.31%,0.56%,and 4.75%)when the sample concentration was 250,25,and 2.5 μg/ml.Conclusion:The method is wide of linear range and is good of the correlation coefficient.This described method is rapid,accurate and cost-saving for the determination of Aniline,N-methylaniline,N,N-dimethylaniline in air.