In line with the increasing development also gives effect to the land use area. There is a one of solution to minimize the land use area is utilize existing buildings (reuse). The concept of adaptive reuse is often imposed on the preserved historic buildings. This building has been through a vulnerable period of more than 50 years that have proven resistant to a variety of things, one of which climate responds. With the approach of adaptive reuse and grounded research, this study aim to the site of the former building Kedaton Tenggarong Kutai in East Kalimantan which now has been converted to Museum Negeri Mulawarman. This building is one of conservation buildings, builded in colonialism that adobted Europe architecture style and adapted to local climate. With sustainable building approach, this research will examine the sustainability of the building after converted into a museum building. In addition to the approach greenship this study will also assess the site conditions of Museum Negeri Mulawarman. Necessary special requirements for certain objects and also the Local Government intervention is required to review the transfer functions of the building
