UNESCO Viet Nam's focus in the Natural Science sector is to ensure sustainable development at the country's geopark, biosphere reserve and world natural heritage sites. Interventions include integrating local customary rights and practices into protected area management, building capacity in tourism management at biosphere reserves, and further developing biosphere reserves as sites for education and research for sustainable development, particularly in relation to growing climate change effects.

A key project in building green economies has been launched at Cat Ba Biosphere Reserve, where an official logo and certification process for labelling “green” goods and services promotes sustainable business practices. Furthermore, the Science sector is implementing “Biosphere Reserves for Environmental and Economic Security” (BREES) in Viet Nam, a long-term regional climate change and poverty alleviation project with a current focus on Cat Ba Biosphere Reserve. UNESCO Viet Nam has been working in close partnership on these projects with Man and the Biosphere (MAB) Viet Nam, the National Commission for UNESCO, and the UNESCO Regional Science Bureau for Asia and the Pacific in Jakarta.

Additionally, the office is actively supporting its counterpart in Jakarta to implement a number of projects for sustainable water management throughout Viet Nam. These include managed aquifer recharge (MAR) projects in Binh Thuan and Ninh Thuan provinces, the former of which is currently being monitored by the UNESCO Regional Science Bureau in Jakarta in partnership with the Vietnamese Academy of Science and Technology (VAST). Based on the success of this project, the Ministry of Science and Technology (MoST) has further requested hydro-geological research along the coast of the Ninh Thuan Province, leading to the launch of a new project on the impacts of climate change on groundwater resources.