Objective: Skeletal muscle is a crucial tissue from the perspectives of mitochondrial dysfunction and insulin resistance, it is formed by myogenesis which is dynamic multistep process to be myotubes. The authors could found that root of Atractylodes macrocephala Koidzumi (Atractylodis Rhizoma Alba, ARA) enhanced glucose and lipid metabolism in C2C12 myotubes via mitochondrial regulation. However its action in myogenesis process is not known. The aim of this work was the study of ARA on proliferation, differentiation and hypertrophy in C2C12 cells. Methods: To study proliferation phase, cells were incubated in growth medium with or without ARA (0.2 or 1.0 mg/ml) for 24 hours. To examine differentiation, at 70% confluence, cells were transferred in differentiation medium both with/without ARA (0.2 or 1.0 mg/ml) for 96 hours. And after 72 hours of differentiation, cells were treated with or without ARA (0.2 or 1.0 mg/ml) for 24hours, the genesis of hypertrophy in myotubes were analyzed. Results: In proliferation phase, ARA could make difference in morphologic examination. In differentiation phase, it also made morphologic difference furthermore ARA (1.0 mg/ml) increased mRNA expressions of Myogenic regulatory factors and muscle-specific proteins synthesis. In late differentiation, ARA induced hypertrophic morphological changes in neo-formed myotubes. Conclusions: ARA might control cell cycle promoting myogenesis and hypertrophy in C2C12 cells.