Rozi, Fahrul2013-04-192013-04-192013-04-19http://repository.unri.ac.id:80/handle/123456789/2936This research is located in Kabupaten Tanah Datar. Economic activity in this place is dominated by natural resources based sector, which are in the field of agriculture, forestry, plantation and fishery. These sectors are the main element of PDRB progress. The aim of this research is to find out agriculture sector which have the biggest contribution in KabupatenTnahDatar. In this research, writer used Location Question (LQ) approach. Measuring technique is done to find out the concentration of such economic activity in an area by comparing economic situation in the province in the same field. Data used is secondary data, gotten from BadanPusatStatistik (BPS) office kota Padang and Tanah Datar. Based on data processing, writer found out that economic sector which is potential to be base sector is agriculture, specifically, food supply. Meanwhile, plantation, animal husbandary, fishery, forestry are also potential, but cannot be base sector yet. The production data in food supply plantation can be seen as follow: in 2008, 3.246128. in 2009, 3.214058. in 2010, 3.310476. in 2011, 3.193278. all data are in million. Writer hope that local government can give stimulation for economic developing in Kabupaten Tanah Datar.otheragriculturebase sectorLocation Quotient