Various trials have been conducted for the management of male pattern hair loss. A variety of laser and light sources have been tried for MPHL. The study objectives were two-fold: 1) To understand the effect of the 1550nm fractional erbium-glass laser on the hair cycle in an alopecia mouse model, and 2) to study the clinical effect of the same laser applied to the treatment of MPHL. In animal experiments, irradiation was applied to shaved skin of C3H/HeN mice with various energy and density settings as well as varied irradiation intervals. In a clinical pilot on human subjects, ten patients were treated on a five-session basis, 2weeks interval, with a fractional photothermolysis laser at energy of 5mJ, total density of 300 spots/cm2. In the animal study, the hair stimulation effects were dependent upon energy level, density and irradiation interval. The anagen conversion of hair and increase of Wnt 5a, β-catenin signals were observed. In the human pilot study, incremental improvement of hair density and growth rate was observed. Result will be discussed the 1550nm fractional erbium-glass laser may be an effective therapeutic tool to treat MPHL along with conventional treatment methods