This article evaluates the competitiveness of irrigated rice produced in Brazil, Uruguay and Argentina, the main partners in the commerce of this cereal. The rice production costs, the agricultural policies, the exchange rates and the common external tariff (CET) in the three countries are analyzed comparatively. The research shows that the rice produced in Argentina is the most competitive of the region, due to the lower production costs per hectare and per bag of 50 kg, followed by Uruguay and Brazil. Regarding the agricultural policy of each country, in Brazil policies are mainly oriented towards rural credit and short term actions, with reduced subsidies for large scale farmers and protection of family agriculture. In Uruguay, the agricultural policies are centered on research, rural assistance, campaigns against diseases and plagues and inspection services. In this country, rural financing is predominantly in US dollars with market interest rates. In Argentina, the farmers are inserted in a market economy without state subsidy. The study also shows that the changes in the exchange policy and the alterations in the common external tariff (TEC) affect the prices of the rice in the region and are prejudicial to competition.