Early Acanthamoeba keratitis was diagnosed in two soft contact lens wearers. Both patients had initially been diagnosed as having herpes simplex keratitis and treated with antiherpes drugs. In one patient, slit-lamp examination disclosed dendritiform epithelial keratitis, subepithelial opacities, linear stromal infiltrate along the corneal nerve (radial keratoneuritis), and marked swelling and hyperemia of the limbal conjunctiva. Acanthamoeba castellanii was cultured from the corneal scrapings and contact lens case. The second patient also showed dendritiform keratitis and subepithelial opacities, with swelling of the limbal conjunctiva. Cultures were positive for A. polyphaga from the contact lens case, but negative from the corneal scrapings. The patients were cured of Acanthamoeba keratitis with medical therapy consisting of topical fluconazole and miconazole, systemic fluconazole, and topical corticosteroids. Recognition of distinctive characteristics of the clinical findings in early Acanthamoeba keratitis can lead to the early diagnosis of the disease.