Abstract: Objective The objective of this study was to elucidate the types of branch and stem diseases in forest trees in Wuwei of Gansu Province.Method Typical symptoms were utilized to investigate the major diseases,and the pathogenic fungi responsible for these diseases were identified through entity isolation,morphological characterization of disease site substrates,and phylogenetic analysis of multi-gene sequences.Result The survey encompassed 40 genera and 58 plant species,with 11 genera and 16 species exhibiting signs of disease.A total of 22 disease types were identified,with poplar（Populus spp.） and acacia（Styphnolobium japonicum） rot disease being the most severe.Seven primary pathogenic fungi were identified by using molecular biology techniques,including Aplosporella africana,Cytospora ailanthicola,Cytospora euonymin,and Cytospora sophoriopsis.Additionally,one new Chinese record and 17 new host records of a forest pathogenic fungus,i.e.,Aplosporella africana,were recorded.Conclusion In Wuwei,poplar（Populus spp.） and acacia（Styphnolobium japonicum） exhibited the most severe rot diseases.