The invention discloses application of graphene quantum dots to prevention and treatment of osteoporosis. The application of the graphene quantum dots to prevention and treatment of osteoporosis concretely comprises application of the graphene quantum dots to preparation of a drug for inhibiting fusion or differentiation and maturation of osteoclast precursor cells, application of the graphene quantum dots to preparation of a drug for resisting the bone resorption capacity of mature osteoclast, application of the graphene quantum dots to preparation of a drug for inhibiting differentiation and fusion of osteoclast or expression of ripening-associated genes, application of the graphene quantum dots to preparation of a drug for inhibiting TRAP enzyme activity of osteoclast, and application of the graphene quantum dots to preparation of a drug for inhibiting fusion of osteoclast precursor cells to form multinucleated mature osteoclast; an effective dose of the graphene quantum dots can inhibit differentiation and maturation of RANKL induced BMMs cells to osteoclast in a concentration-dependent manner, inhibit bone resorption capacity of osteoclast obtained by differentiation and maturation of the RANKL induced BMMs cells, and further inhibit fusion of osteoclast; besides, the graphene quantum dots can obviously reduce expression of osteoclast differentiation specific genes, therefore the graphene quantum dots finally achieve the function of preventing and treating osteoporosis, and further can be applied to prevention and treatment of osteoporosis.