Abstract :
Ogan Komering Ulu has an amazing variety of historical and cultural richness. One such heritage is the traditional architecture of the Rumah Ulu. This research is a qualitative research with etnograpic approach. The purpose of this study is to describe the names of parts Rumah Ulu and the introduction of flat structures and angle measurements. Data obtained from the results of observations, documentation and informants. The subject of this research is the shop and also the owner of the Rumah Ulu. Data analysis techniques using the theory of Milles and Huberman. Sources obtained from the result of observations, documentations and informants. The tools used in the form of interview guidelines and observation guidlines. The result showed that each part of Rumah Ulu had mathematical elements such as flat shapes and angle measurements. Therefore, learning culture-based mathematics is neededin school especially at the elementary school level.