Based on the work of Jensen [Jensen, S.S., 1998. Mapping human exposure to traffic air pollution using GIS. Journal of Hazardous Materials 61(1-3), 385-392; Jensen, S.S., 1999. A geographic approach to modelling human exposure to traffic air pollution using GIS. Ph.D. Thesis. National Environmental Research Institute, Roskilde], a prototype system for modelling noise and air pollution is developed for the Macao Peninsula. The system integrates a road traffic noise model, an operational air pollution model, digital maps, an urban landscape model and a Geographic Information System (GIS). Compared with mesoscale model systems with input/output resolution in kilometres, the present one has a higher spatial resolution down to individual buildings along both sides of the street. Applying the developed model system, a preliminary study investigates the ways that four urban forms existing nowadays on the Macao Peninsula influence vehicle transport and street environment. This paper shows that the urban forms in historical areas with narrower roads, complex road networks and a higher density of intersections lead to lower traffic volumes and thus lower noise pollution. However, the greater street canyon effects in these historical urban areas lead to higher carbon monoxide (CO) concentrations. © 2007 Elsevier Ltd. All rights reserved.