A series of field investigations and tea collections were conducted in the West Lake Tea Plantation of Hangzhou. The authors aimed to search for the main source of Pb contamination by measuring Pb isotope compositions in soils, tea, coal, automobile exhausts, and aerosols. The results show that the dissoluble lead is homogenous whereas the residual lead is heterogenous. Lead content of the rinsed tea decreases evidently, whereas Pb isotope compositions do not vary significantly. In addition, Pb in tea is derived from the same source as that in the atmospheric deposition. The 206Pb/207Pb ratio in topsoils, aerosols and coals is similar to that in tea. At the same time, the 208Pb/(206Pb+207Pb) ratio in topsoils, aerosols and gasoline is similar to that in tea, but the Pb content of coals is somewhat higher. Lead in tea is homogenous and has nothing to do with the background values of different tea plantations. The adsorption and uptake of lead by tea are completed by atmospheric deposition in the process of coal gasification and combustion. In addition, the automobile exhaust is one of the main sources of lead contamination.