The constant increasing emissions of carbon dioxide (CO2) into the atmosphere is causing an ecological and anthropogenic disaster. CO2 has been considered a major cause of the greenhouse effect that is leading to global warming. India accommodates around one million industries of small, medium, and large sizes, such as petrochemical, chemical, steel, rubber, polymer, and agrochemical industries. Every year, seven million metric tons of petroleum products, ten million tons of rubber, and fifteen million tons of polymer are produced and one million tons of CO2 flu gas and five million tons of untreated waste are produced. In the present scenario of the CO2 adsorption process, various physical and chemical treatment techniques, that is, ion exchange, filtration, and adsorption methods, are available. They are highly expensive and pollute the environment by releasing secondary contaminants into the environment. As an alternative, the ecofriendly, naturally available low-cost microalgal system could be utilized more than 20 times more efficiently than terrestrial plants and physical and chemical methods to remove the CO2 from the environment. In the bioadsorption process, RuBisCO and Acetyl CoA carboxylase enzymes are involved and enhance the major process in algal cells for CO2 adsorption and utilization. Photosynthetic organisms convert atmospheric CO2 to energy, increasing CO2 bioadsorption and serving as an essential climate change approach. This book chapter explains the mechanism of CO2 capture and mass cultivation methods of microalgae for CO2 sequestration. © 2022 Elsevier B.V., All rights reserved.