In 2017-2018, extensive symptoms of sudden decline and fruit rot were observed on date palms in southern Tunisia. Samples of diseased plants were randomly collected in six localities. Based on morphological identification, was the most frequent fungal genus detected. A sequencing of translation elongation factor, calmodulin, and second largest subunit of RNA polymerase II genes was used to identify 63 representative strains at species level and investigate their phylogenetic relationships. The main species detected was , and at a much lesser extent, , , , and . Pathogenicity on the variety plantlets and the capability to produce mycotoxins were also assessed. All species were pathogenic complying Koch's postulates. strains produced mainly fumonisins (FBs), beauvericin (BEA), and, to a lesser extent, enniatins (ENNs) and moniliformin (MON). All strains produced low levels of BEA, diacetoxyscirpenol, and neosolaniol; two strains produced also T-2 toxin, and a single strain produced HT-2 toxin. , , produced only BEA. strains produced MON, BEA, and ENNs. This work reports for the first time a comprehensive multidisciplinary study of species on date palms, concerning both phytopathological and food safety issues.