Air pollution is an important aspect for transportation, particularly car emission in urban area. The objective of this paper is to evaluate the global emission of a transport network based on probe car and traffic sensor data. This paper used the microsimulator; AIMSUN to simulate vehicles on a network and also the pollutant emitted. Different penetration rate of probe vehicles were simulated and the accuracy of pollutant estimated from probe vehicles were compared against the emission from the all vehicles simulated i.e probe and normal vehicles. Two spatial resolutions i.e. at a network level and at a link level were studied. This paper shows that probe car can be used to give good estimate of pollutant emitted by vehicles traversing on a network. Depending of the network configuration, a penetration rate of 5- 10 % of probe car is sufficient to obtain satisfactory results of the global emission data.