Global warming and climate change are major concerns in every domain of the earth. Recently, there was an increase in global atmospheric carbon dioxide (CO2) concentration (64.05 ppm) from 1980 to 2016 due to enhancement of fossil fuel burning and alteration in land use related with population growth and industrialization. This increased atmospheric concentration can be managed by the combination of reduced emissions and mitigation strategies by enhancing natural carbon storage i.e., biosequestration of carbon. Algal carbon sequestration and carbon storage plays important role in mitigating global problem of CO2 pollution, especially microalgal carbon sequestration through the photosynthetic pathway facilitate the remarkable reduction of atmospheric CO2 and act as a promising alternative biological tool for biological carbon sequestration. Therefore, microalgae are promising organisms for bio-mitigation, because 1.83 kg of CO2 can be fixed via cultivating one kilogram of microalgae. Recently, there is a number of algal based CO2 Capture Pilot Plant that has been established around the world. Among the various alternatives to carbon capture and utilization, microalgae cultivation is currently one of the less mature and economically practicable technique. From these points of view, the present chapter focused on the algal carbon sequestration and storage mechanism, and role of microalgae in carbon sequestration and capture with pilot scale case studies on algae based carbon capture. This green technological innovation of algal carbon sequestration is important, which is one of the prime solutions in future prospect in mitigating the global CO2 problem.