Abstract: We used quantitative real-time RT-PCR to investigate the tissue expression patterns of cytokinin bindingprotein PdCYTOB, which is related to the wood properties of Populus deltoides. PdCYTOB was expressed predominantly in immature xylem, immature phloem and the phloem zone of the stem of P. deltoides. Southern blot and RT-PCR were used to detect antisense PdCYTOB-transgenic Populus davidiana × P. bolleana plants. The antisense PdCYTOB gene was integrated into the genome of the poplar and expressed. Phenotype, anatomical studies and microfibrillar angle analysis revealed the plant height of transgenic poplar higher than that of untransformed lines, as well as xylem and the phloem zone of plants with antisense PdCYTOB wider than those of untransformed lines. In addition, the microfibrillar angle of transgenic plants was decreased in the test field. Thus, pulping and papermaking properties might be improved in antisense-PdCYTOB transformed lines. Our study sheds light on the molecular mechanism of PdCYTOB in wood formation in P. deltoides.