This review specifically deals with the latest advances in the application of nanotechnologies and nanocomposites for remediation of arsenic (As)-contaminated water and soil. Remediation mechanisms generally include physicochemical adsorption and (photo)chemical redox reactions and filtration. Recently, various types of engineered organic/inorganic nanocomposites have been designed in membrane forms, embedded structures, or composites with extraordinary physical-chemical properties, and outstanding capacity for removal or immobilization of As in contaminated sites. In the present article, we give an overview of engineered nanomaterials developed recently (2017-2021) and their interaction mechanisms with As in contaminated water and soil. Emerging approaches include the development of bio-nanocomposites and nanomaterials that show both oxidative and adsorptive capacities. For the first time, we set out to perform a comprehensive assessment of the advantages of nanomaterials in As-contaminated soils with the focus on the mechanisms of decreasing bioavailability and leaching of As. Although great researches have been developed, serious study gaps and a new direction to future researches have been identified. © 2021 Elsevier Ltd.