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Species of <i>Cytospora</i> are considered important plant pathogens of a wide range of plant hosts, especially Salicaceae plants. <i>Salix</i> (Salicaceae, Malpighiales) has been widely cultivated in China because of its strong ecological adaptability, fast growth, and easy reproduction. In this study, a total of eight species of <i>Cytospora</i> were discovered on <i>Salix</i> in China, including <i>C. ailanthicola</i>, <i>C. alba</i>, <i>C. chrysosperma</i>, <i>C. gigaspora</i>, <i>C. nivea</i>, <i>C. paracinnamomea</i>, <i>C. rostrata</i>, and <i>C. sophoriopsis</i>. Among them, <i>C. alba</i> and <i>C. paracinnamomea</i> were identified as novel species based on morphology and phylogenetic analyses of ITS, <i>act</i>, <i>rpb2</i>, <i>tef1-α</i>, and <i>tub2</i> gene sequences and were confirmed as pathogens of willow canker disease by pathogenicity tests. The mycelial growth rates of strains from these two novel species (<i>C. alba</i> and <i>C. paracinnamomea</i>) had optimum temperatures of 21 to 22 °C and an optimum pH value of 5 to 6. The effectiveness of six carbon sources on the mycelial growth showed that fructose and maltose had the highest influence. <i>Cytospora</i> species richness was significantly positively correlated with dry and wet areas. This study represents a significant evaluation of <i>Cytospora</i> associated with willow canker disease in China and provides a theoretical basis for predicting the potential risk of willow canker disease.