This paper describes current status and future prospects of the mass production of microalgae biomass. Microalgae have attracted considerable attention since they not only effectively fix $CO_2$ gas during their metabolic process but also have the great potential to be utilized for producing valuable substances as a kind of efficient light-harvesting cell factories. In this review, we outline various types of photobioreactors employed for mass production of biomass by culturing microalgae in a well controlled way and give an overview about the present state of affairs, both domestic and international, in the field of the microalgal culturing technologies.