Teeth are covered by enamel over the coronary portion and by cementum over the root. When teeth suffer some kind of aggression those protections may be removed exposing dentin, leading to dentin hypersensitivity. There are several ways to treat such clinical condition, among them low level laser therapy (LLLT). The purpose of this research was to verify the LLLT efficacy in dental hypersensitivity treatment. There were selected 10 patients, presenting 50 teeth showing dental hypersensitivity. Patients had 03 appointments using LLLT within 03 weeks. The device used was Gallium Arsenate – aluminum (Bio Wave Red® - Kondortech). Results were analyzed with MANOVA statistic test and it was observed a sensibility reduction after the first therapy significantly greater than the last therapies.