[Objective] The research aimed to understand the levels of indoor air particles of PM10 and PM25in public places in Chaoyang District ofBeijing City, which will provide scientific basis for making health standards and policies and regulations of indoor air particulate matter in public places. [Method] In order to characterize indoor air quality of public places, shopping mall near the walking street, shopping mall near arterial traffic,barbecue style restaurant and eat hutch unicorn Chinese restaurant were selected for this study. LD-3C laser measuring dust detector and Sidepak AM-510 artificial intelligence ant卜explosion dust detector were used to test the levels of PM10 and PM2.5 in the air of the shopping malls and restaurants. The number of smoking customers and if smelling the smoke were recorded simultaneously. [Result] The average densities of PM10and PM2.5 in the shopping mall near the walking street were noticeably lower than that near arterial traffic (P<0.05). The highest level of PM2.5 at the barbecue style restaurant and eating hutch unicorn Chinese restaurants were 1090 and 666g/m3. The average levels of PM10 at the barbecue style restaurant and eating hutch unicorn restaurants were 286 and 399g/m3(P<0.05). [Conclusion] The indoor PM10 and PM25 concentrations were high in public places, especially in shopping mall near arterial traffic and restaurant. It should be enhanced to supervise indoor air in public places and establish the risk rating of indoor air quality to protect public health.