Bener Subdistrict is one of the sub-districts in Purworejo District that implements an organic rice farming system through Go Organic development in 2010. However, going to pure organic takes a long time so that until now it is still called semi-organic rice. There are three villages that apply semi-organic rice with different backgrounds. Bleber Village is the longest village since 2007 in conducting semi-organic rice, Ngasinan Village since 2014 because it received assistance, while Legetan Village implemented semi-organic rice because of its own initiative. Sampling by the census is 75 farmers. This study aims to analyze the production factors that influence the semi-organic rice production and analyze the level of technical, price and economic efficiency. Data were analyzed using the production function of the Cobb-Douglas Stochastic Frontier model. The results showed that the variable area of land, seeds, manure, NPK fertilizer, phonska fertilizer, and dummy seed varieties significantly affected semiorganic rice production. Technically, farmers have been efficient with an average index of 0.725 and economically efficient with an average of 0.924. But the price of farmers is not yet efficient because the average level of efficiency is more than 1, which is 1,352. Meanwhile, from the six internal factors of farmers, age, farming experience, education level, the dummy of Bleber Village, Ngasinan Village and Legetan Village has no effect on inefficiency.