Aquifer-based geogenic processes are frequently responsible for the prevalence of arsenic in aquatic habitats. Pentavalent arsenate is less harmful to aquatic biota than trivalent arsenite, which is one of the two common oxidation states of arsenic. Conventional physical and chemical techniques such as oxidation, filtration, and adsorption have been examined for arsenic removal; however, these techniques frequently have high operating expenses, poor efficiency, and difficult disposal situations for hazardous waste. Biological treatment methods offer a cost-effective and sustainable way to minimize arsenic pollution. This chapter looks at the bioremediation of arsenic-poisoned environments using plants and microorganisms such as bacteria and fungi. Important mechanisms such as bioaccumulation, biotransformation, and biovolatilization that contribute to the immobilization of arsenic within biological matrices or its transformation into less hazardous forms are emphasized. The chapter also examines potential integrations of these biological systems with other treatment modalities to increase efficacy. It also covers the limitations and real-world problems associated with applying bioremediation strategies. Future directions in genetic engineering and management of the microbial community are also explored as means of refining biological arsenic cleaning methods.