Ectodermal dysplasias are a group of hereditary disorders with improper development of embryonal ectodermal layer. The diagnosis of these disorders is challenging during infancy and it must be considered while investigating infants or neonates with fever without focus and dehydration. In the infants , clinical signs of this condition are subtle and non-specific. The classical signs of the disease become more visible after a few months of life. Paediatricians should have high index of suspicion of anhidrotic ectodermal dysplasia in infants or neonates presenting with fever without focus and dehydration especially in summer season. We report this rare clinical entity and supplicate to consider the diagnosis of anhidrotic ectodermal dysplasia when investigating pyrexia of unknown origin (PUO) or hyperthermia in infants during summer especially in areas of semi arid climate and dry weather.