Zymoseptoria is a new fungal genus comprising seven species that all are pathogenic on cereals and wild grasses. During surveys on Poaceae plants in 2012 in East Azarbaijan province, Agropyron repens plants showing symptoms similar to Zymoseptoria infection were sampled and fungal isolates were isolated from infected leaves. Based on morphological characteristics and phylogenetic analysis of ITS and β-tubulin gene sequences, the causal agent was identified as Z. ardabiliae. This is the first report of the fungus from East Azarbaijan province.