A new and distinct peach variety of Prunus persica named `NJF18` is provided. This variety is distinguished from other peach varieties by its unique combination of showy flowers that are medium in width, flat fruit that ripen in early midseason with mottled red over color on an attractive orange ground color, semi-clingstone fruit with a juicy, melting texture and sweet, mild flavor, firm fruit that retain their firmness well and trees with regular, heavy production of large fruit.