This study aimed to determine indoor and outdoor levels of volatile organic compounds (VOCs) and to assess potential risks among residents living in the vicinity of an optoelectronics industrial park in 2006–2007. We used steel canisters to collect 72 indoor samples and 80 outdoor samples over 24 h. Gas chromatography with a mass-selective detector was used for qualitative and quantitative analyses. The amounts of time residents spent doing activities in different microenvironments were determined by the self-administered questionnaire. The chronic hazard index (HIc) and cancer risk were applied to assess the non-carcinogenic and carcinogenic risks of VOCs among residents. Four VOCs of ethanol (indoor: 77.8 ± 92.8 μg/m3; outdoor: 26.8 ± 49.6 μg/m3), toluene (67.0 ± 36.7 μg/m3; 56.9 ± 19.0 μg/m3), m/p-xylene (50.8 ± 66.1 μg/m3; 21.2 ± 20.3 μg/m3), and acetone (37.7 ± 27.5 μg/m3; 25.8 ± 9.8 μg/m3) were identified as dominant components in both the indoor and outdoor environments. Total VOCs and six VOCs of benzene, toluene, ethylbenzene, m/p-xylene, o-xylene, and ethanol in indoor sites were significantly higher than those in outdoor sites (all p-values < 0.05). All estimated HIc values were less than unity and the cancer risk of benzene exposure was 1.8 × 10−4 (range: 9.3 × 10−5 to 3.4 × 10−4) based on resident time-weighted patterns. Strategies to reduce benzene exposure should be implemented to protect public health.