ABSTRACT: The exposure of 60 bus drivers and 60 bus conductors were assessed for volatile organic compounds (VOCs) in air-conditioned (A/C) and non-A/C buses on the three routes. VOCs were collected with personal passive sampling and analysis by GLC. The subjects were interviewed with questionnaire. The health risk was assessed for the drivers and conductors following the US. Environmental Protection Agency (EPA) method for benzene. The bus drivers in non-A/C buses developed sore throat and phlegm was 9.71 and 4.86 times of those in A/C buses and the bus conductors in non-A/C buses reported sore throat and cough was 3.13 and 3.03 times those in A/C buses. The lifetime cancer risk of bus drivers´exposure to benzene was 1.5x10-4 and 2.1x10-4 for A/C and non A/C buses, respectively. The lifetime cancer risk of bus conductors was the same (2.2x10-4) for A/C and non A/C buses. The bus driver and conductors should wear respirator with cartridge or reduce number of hours working to reduce exposure to benzene.