In 83-93% of the cases of acanthamoeba keratitis the patients are contact lens wearers. Acanthamoeba keratitis is diagnosed--with descending order of sensitivity and specificity--through polymerase chain reaction (PCR), confocal biomicroscopy, in-vitro cultivation and histopathological examination. The typical clinical appearance of acanthamoeba keratitis includes pseudodendritic epitheliopathy, perineuritis, ring infiltrate or multifocal stromal infiltrates and in some cases limbitis with infiltration of the conjunctiva and/or sterile anterior uveitis. Information on reliability and efficacy of the medical/surgical therapy for acanthamoeba keratitis has only been published for case series and It has not been verified through randomised controlled clinical studies so far. By early diagnosis, using triple-topical therapy (polyhexamid, propamidinisoethionat, neomycin) acanthamoeba keratitis often heals appropriately. However, even if diagnosed early, topical therapy should be continued for 1 year. In therapy-resistant cases cryotherapy, amniotic membrane transplantation, cross-linking therapy, and therapeutic keratoplasty are performed. The prognosis of keratoplasty following acanthamoeba keratitis is more favourable when there were no signs of infection at least during the preceding 3 months.