During the peak and off-peak dining time, smoke emitted from big and medium-sized barbecue restaurants and small roadside barbecue stands was detected. It was found that TVOC concentration at the peak time reached to 2~3 times of the environmental background value. TOVC concentration of the smoke from small roadside stands was the highest, then was the medium-sized barbecue restaurants followed by the big ones. Variation of benzene and xylene showed a certain difference. That is, the concentration of benzene tended to decrease after the dining peak, while that of xylene increased slowly because free radical reaction was weakened but still lower than that at the peak time. The exposure doses of benzene and xylene at the peak time were higher than those at the off-peak time. The exposure dose of outdoor barbecue stands was significantly higher than that of the big barbecue restaurants but similar to that of the medium-sized ones. In the whole sampling environment, the carcinogenic risk of benzene was not high but still existed. Xylene could not have obvious non-carcinogenic effect on health of the exposed population group.%用餐高峰期和非高峰期分别对大型烧烤店、中型烧烤店和小型路边烧烤摊排放的烟气进行检测，发现TVOC浓度高峰期达到环境本底值的23倍，小型室外烧烤摊>中型烧烤店>大型烧烤店；苯与二甲苯变化规律呈现一定差异性，苯高峰期后浓度呈下降趋势，而二甲苯由于自由基反应减弱浓度缓慢升高，但仍低于高峰期浓度；苯、二甲苯的暴露剂量高峰期大于非高峰期；室外烧烤摊的暴露剂量明显大于大型烧烤店，与中型烧烤店相差不大；整个采样环境下苯不存在较高致癌风险，但仍然存在致癌风险；二甲苯不会对暴露人群造成明显的非致癌健康影响。~
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