Abstract: Alternaria polypodiicola sp. nov., is described, illustrated and discussed, causing foliar disease on a pteridophytic plant Microsorum punctatum (Polypodiaceae) from Uttar Pradesh, India. The present species was compared with closely similar species based on morphological characters. This species is characterized by having well developed stromata, unbranched and shorter conidiophores with shorter smooth conidia. A key is provided to all species of Alternaria reported on Polypodiaceae. The description and nomenclatural novelty details were deposited in Mycobank.