Oil palm is a significant agricultural crop, highly valued for its role in oil production. This study identified two fungal pathogens, Diaporthe phaseolorum and Neopestalotiopsis clavispora, as causal agents of leaf spot disease in oil palm (Elaeis guineensis), marking their first reported occurrence. Over 85% of surveyed trees in Pahang, Malaysia, were affected, posing a significant threat to oil palm productivity. Morphological, pathogenicity and molecular analyses confirmed their roles, with Lasiodiplodia theobromae causing the most severe lesions. These findings underscore the importance of early detection and targeted management to mitigate economic losses.