This research's objective aims to determine the factors of production that influence siam oranges production and to analyze the efficiency of production factors on siam orange farming in Batang Hari Regency. In this research, a restriction was conducted on the analysis of the factors that affect the production of siam oranges, that productive trees, organic fertilizer, chemical fertilizers, pesticides, and labor. The research was conducted in Senaning Village, Pemayung District and Pompa Air Village, Bajubang District. The selection of the study sites was purposive sampling and deliberately determined on the basis those villages were production areas of siam oranges in Batang Hari Regency. The functional form of production function was the Cobb-Douglas model and to see the level of efficiency of using production factors on siam oranges farming used allocative efficiency analysis. Based on the results of this study factors of organic fertilizers and labor significantly affect siam oranges production. Generally, siam oranges production was relatively responsive to the number of production factors used. The use of factors production i.e. productive trees, organic fertilizer, and chemical fertilizers were relatively efficient but the pesticide and labor variable was not. There were productivity differences between siam orange farming in Senaning Village and Pompa Air Village. Government and societies should concern a suitable agroecological and skilled farmers to develop a new area production of siam oranges in Batang Hari Regency.