Uganda’s rice demand has been on an increase due to increasing population, urbanization and changing consumer preferences. The resulting effect has been increased importation of rice into the country consequently straining foreign exchange accounts. Insufficiency in the rice supply is related to the low national average yield of 1.5t/ha. New upland rice varieties that are high yielding have been introduced in the country to improve national supply, save wetlands, fight food insecurity and improve incomes of the rural poor. This study was conducted in South Western Uganda in the districts of Bushenyi and Rukungiri. It examined whether farmers were technically efficient in input use to generate the required output levels and the farm specific factors that were affecting their technical efficiency. A total of 196 respondents were randomly selected from four rice producing sub counties using a sampling frame generated by the sub county leaders. A Cobb Douglas production function was fitted to the data to generate results. Analysis was accomplished using frontier 4.1 programme. Results revealed that production of upland rice involved excessive use of labour (1136 person days/ ha) and seeds (154kg/ha) compared to the recommended rates. It was also found that technical efficiency of upland producers were below the frontier level averaging at 61% and the existing output was being achieved through land expansion. Attainment of primary five education significantly (P=0.076) improved efficiency of farmers. For farm level technical efficiency of upland rice to improve, yield improving and labour saving technologies need to be introduced notably soil enriching aspects like fertilizers. For labour saving technologies, use pre or post emergency herbicides and mechanization of the upland rice would be a better move in the right direction. Lastly promoting primary education and specialised extension services that target upland rice will improve efficiency greatly.