McCune-Albright syndrome is a rare G proteins α disorder. The disorder is characterized by polyostotic fibrous dysplasia, sexual precocity and hyperpigmented macules. It is caused due to mutations in the gene Gsα that incodes the α subunit of the trimeric guanosine triphate-binding protein. There is no specific treatment for this syndrome. Treatment is generally symptomatic. This paper reported three cases of McCune-Albright syndrome and reviewed the relevant literatures regarding to the pathogenesis, pathological features, diagnosis and treatment. All three cases presented with a characteristic triad: polyostotic fibrous dysplasia, sexual precocity and hyperpigmented macules and were thus definitely diagnosed with McCune-Albright syndrome.