The results of spatial and temporal distribution of volatile organic compounds (VOCs) in ambient air surrounding the Hsinchu Science-Based Industrial Park (SBIP), Taiwan during February 2001 to November 2001 are presented. The sampling was performed at 13 different sites around the SBIP for 24 hrs once every month, and a total of 130 samples were collected. The effects of geographical and meteorological conditions and production volume of the SBIP on the variation of pollutant’s concentration were investigated. The spatial distribution shows that a comparatively higher concentration of VOCs was found at the sites, which are in the southwestern part of SBIP, downwind of or close to factories. When the wind velocity was low (i.e. below 2 m/s), the concentration of pollutant tended to increase and became uniformly distributed around the science park. The temporal distribution shows a decrease in ambient concentration of pollutants from February to June 2001, mainly due to the decline in the production volume of the SBIP in this period. During the whole period of investigation, the concentration of most of the compounds (except acetone and IPA) was found to be lower than the factory-surrounding air quality standard of Taiwan, but in some cases it was higher than the AALG (ambient air level goal).