Green Leaf Organization (GLO) is a local Non-Governmental Organization established in Katavi Region and registered on 19 Sepember, 2016 under NGOs Act, 2002 by the Ministry of Health, Community Development, Gender, Elders and Children in Tanzania mainland with registration number 00NGO/0008894.

The main Founder members of GLO are Arnold Vitalis Lumbi and Fransice Ferdinand Filimbi. These participated fully in establishment of this organization due to the severe destruction of the environmental especially Forestry and Water sources in Western Regions of Tanzania maniland including Katavi and Kigoma Region respectively. People were looking for fertile land in order to conduct agricultural's activities. So, they migrated from their drought areas to Katavi and Kigoma Region to look for fertile land. Thus, agricultural activities contributed much in environmental deterioration in Katavi and Kigoma Region. Also, some of the areas of the Games Reserve  and National Parks likely Katavi National Park and Kaseganyama Game Reserve were attacked by the migrants from various parts of Tanzania's Regions loooking for agricultural land and pasturing areas for their Cattle.

Improvement of the livelihood of the local community members is the overall objective of the Green Leaf Organization in conservation of environmental and promotion of Tourism. 

Since its establishment, the GLO has succeeded to open an Office at Mpanda District in Katavi Region. This is the head quarter of the Green Leaf Organization. Also, the Field or Regional's Coordination Office has opened at Kigoma District in Kigoma Region.