Solid state fermentation has the obvious superiority in production of biologics and biological treatment process.Especially in recent years,with the development of theoretical model and bioreactors,the application range of solid state fermentation is growing fast.In aerobic solid state fermentation systems,oxygen mass transfer is often one of very important limiting factors for optimal growth and productivity.It is related to restriction of the scale-up of solid state fermentation.This paper reviews the phenomena of oxygen mass transfer process in macroscale and microscale solid state fermentation system.It highlights several control strategies for improving gas transfer efficiency in solid state fermentation.The application prospects of solid state fermentation are discussed at the end of paper.