Doping Al atom was performed to improve the hardness of GaSe crystal. The Al-doped GaSe (Ga<sub>0.49</sub>Se<sub>0.50</sub>: Al 0.15 wt.% and Ga<sub>0.49</sub>Se<sub>0.50</sub>: Al 0.35 wt.%) were grown by the modified Bridgman method with crucible rotation technique. Compared with pure crystal, the hardness of Al-doped GaSe crystals is increased markedly (2.6 and 3.2 times). The GaSe: Al crystal hardness increases with Al concentration increase, but high Al concentration leads to the optical quality degradation (Ga<sub>0.49</sub>Se<sub>0.50</sub>: Al 0.35 wt.% possesses lower optical quality). Therefore, the selection of appropriate Al-doping level is important for the application of GaSe: Al crystals.