Onychomycosis refers to fungal infection of the nails. Toenails or fingernails can also be affected, but it is usually more common for toenails. Infected nails can be discolorated in yellow, apparantly thickened and become chalky. Onychomycosis can have a great impact on the quality of life of patients. Patients may experience pain and discomfort especially during walking and doing exercises. There is cosmetic embarrassment and lowered self-esteem due to disfigurement of affected nails. Diagnosis mainly by typical appearance and confirmed by nail sampling for fungal microscopy and culture. Treatment includes topical and oral antifungal agents, laser treatment or nail avulsion surgery in severe cases.