Melanonychia is defined as brown or black pigmentation on a nail caused by melanin and other exogenous pigments. While the most common causes are benign nevi, trauma, onychomycosis, or medications, melanonychia may be a result of a subungual melanoma. When it is the result of a benign condition, patients may desire treatment for aesthetic reasons. The 755-nm Alexandrite Q-switched laser causes highly selective destruction of pigment-laden cells because the wavelength is highly absorbed by melanin relative to other optically absorbing structures in the skin. This laser is effective for both epidermal and dermal pigmented lesions. Here, two cases of melanonychia combined with onychomycosis that were treated using a single session of 755-nm Alexandrite laser with successful resolution were described.