Abstract: Clematis chinensis black spot severely occurred in Jingxi, Guangxi. An pathogen was isolated from diseased lesions on the leaves of Clematis chinensis ,and its pathogenicity to Clematis chinensis confirmed by inoculation tests. The pathogen was identified as Alternaria alternata (Fr.) Keissler based on its morphological characteristics and ITS sequence. Screening tests of the fungicides indicated that 25% bromothalonil WP, 72% Mancozeb+cymoxanil WP, 30% Armure EC, 80% thiram+Zinc bis dimethyldithiocarbamate WP, 10% difenoconazole WDG all showed good inhibition against mycelial growth, with inhibition rate greater than 90%. This is the first record of Clematis chinensis black spot caused by A. ahernata in Guangxi.