Abstract:215 clones of Populus tomentosa, collecting from different geographic localities in China, were inoculated with leaf rust fungi (Melampsora magnusiana) in the green house in Beijing Forestory University. The infection of the clones on natural occurance were investigated in Shandong provance. Results showed that the resistance of poplar clones to the leaf rust fungi was distinctly different. Clones of South-west Shanxi, South-east Gansu and the South of Shanxi are more resistant than that of Henan, the South of Hebei and the West of Shandong. The most resistant clones contributed mainly in South-west Shanxi, whereas the most susceptible ones, in the South of Henan