Abstract: In order to explore the response of LBD12 gene of Chinese white poplar（Populus tomentosa） to stress, the promoter sequence of PtoLBD12 gene was cloned from P. tomentosa by PCR technique in this stu-dy. The cis-acting element of PtoLBD12 gene promoter was analyzed by bioinformatics technology, and its spatio-temporal expression pattern in response to different stress signals was analyzed. Finally, the GUS reporter plant of P. tomentosa was constructed by using this gene promoter to drive GUS reporter gene. The transgenic plants were treated with different stresses and the promoter activity was analyzed by GUS staining. The results showed that the cloned PtoLBD12 gene promoter had a variety of cis-acting elements, including a large number of light response elements, defense and stress response elements（TC-richrepeats）, abscisic acid（ABA） response elements, methyl jasmonate（MeJA） response elements, auxin（IAA） response elements and gibberellin（GA）response element. Tissue expression pattern analysis result showed that PtoLBD12 gene was mainly expressed in roots and stems, but less in leaves. Based on the analysis result of the response patterns of PtoLBD12 gene to different stress signals, it was found that the expression of PtoLBD12 gene of P. tomentosa was significantly induced by high temperature, low temperature, ABA and IAA. In summary, the experimental results showed that PtoLBD12 is closely related to the response of P. tomentosa to stress, and the gene can respond to a variety of stress signals. This study provides an important theoretical reference for further elucidating the molecular mechanism of PtoLBD12 gene regulating stress response of P. tomentosa.