More than just a cosmetic concern, onychomycosis is a prevalent and extremely difficult condition to treat. In older and diabetic populations, severe onychomycosis may possibly serve as a nidus for infection, and other more serious complications may ensue. Many treatment modalities for the treatment of onychomycosis have been studied, including topical lacquers and ointments, oral antifungals, surgical and chemical nail avulsion, and lasers. Due to their minimally invasive nature and potential to restore clear nail growth with relatively few sessions, lasers have become a popular option in the treatment of onychomycosis for both physicians and patients. Laser or light systems that have been investigated for this indication include the carbon dioxide, neodymium-doped yttrium aluminum garnet, 870/930-nm combination, and femtosecond infrared 800-nm lasers, in addition to photodynamic and ultraviolet light therapy. This systematic review will discuss each of these modalities as well as their respective currently published, peer-reviewed literature.