Abstract: Optimized conditions for the determination of Pb in leaves of navel orange tree by hydride generation-atomic fluorescence spectrometry were studied.The leaves were collected from the urban trees at different crossroads of the Wenming Road.As demonstrated by experimental results,the lead content in leaves was positively correlated with the vehicle flowrate.Linearity of the method was in range within 1.50 mg·L-1 with correlation coefficient 0.997 8.Detection limit of the method was found as 0.19 μg·L-1,and values of recovery were obtained in the range from 93.2%-105.0%.