A microalgae cultivation module includes a supporting structure, at least one circular tube-shaped cultivation bag, a medium and a gas input equipment. The supporting structure has a plurality of positioning portions on its two sides, respectively, and two ends of the circular tube-shaped cultivation bag are respectively fixed on the positioning portions of the two sides in the supporting structure. The medium fills the circular tube-shaped cultivation bag, and contains a microalgae species. The gas input equipment is connected to the circular tube-shaped cultivation bag to input gas to the circular tube-shaped cultivation bag. When the circular tube-shaped cultivation bag is disposed on the supporting structure, the inner part of which is wholly connected, and the cross-section in the longitudinal direction of the circular tube-shaped cultivation bag is arc shaped.
