Asperisporium alstroemeriae (Allesch.) Maubl., the causal agent of leaf spot on Alstroemeria spp., is recorded for the first time in Argentina on commercial hybrids and on the native species A. psittacina. It appears that cultivated hybrids of Alstroemeria spp. and A. psittacina are new hosts for this pathogen. Disease symptoms and fungal description are provided.