This paper deals with the hybrid of Populus pseudo-simonii Kitag. x P. nigra L. in comparison with its parents of P.pseudo-simonii Kitag. The results show that hybrid grows faster than its parents and other features are not much difference, for example, fiber characteritics, vessel element characteristics, wood density and so on. These two poplar species can be used for paper making in juvenile trees. The increase of the width of ring is due to the increase of the number of cells.