This study aims to estimate technical efficiency in rice production and analyze the factors affecting technical efficiency in rice production in KienGiang Province, Mekong Delta, Vietnam. Data were obtained from 276 rice farmers under four cooperatives in Chau Thanh District. Cobb-Douglas stochastic frontier model was applied. The findings show that the farmers occupy, on average, 1.6 ha of rice land per household. The average rice yield was 6.66 tons per ha in summer-autumn crop. The farmers achieved, on average, 92.4% technical efficiency in rice production. The farm size, potassium active and labor hours affect positively the technical efficiency. It was also found that farmers, who have higher experience in rice production and attended in many technical training classes, have obtained higher technical efficiency. However, farmers who joined cooperatives for a long time, but did not join in cooperative activities, cannot improve the technical efficiency.