The objectives of this study were to study the efficiency of input factors for Khao Dawk Mali (KDML) 105 production, and estimate the technical efficiency score of rice production in Roi-Et province. The data used in this study was the cross-section data from famers who grew KDML 105 rice with broadcasting technique in Roi-Et province during 2012/13 crop year. The data was collected using the procedure of purposive sampling by choose highest number of farmers who grew KDWL 105 and found the soil group no 17 and 22 in the same area together with random sampling method. The sample consisted of those who grew KDML 105 rice on soil group no 17 and 22. There were 40 samples for each soil group totalling 80 samples. The result of Cobb-Douglas production function revealed that factors significantly affecting the KDML 105 rice were amount of seed, amount of fertilizer and dummy variable of soil group. The estimate result was also found that the rice production in Roi-Et province was decreasing return to scale. The estimate result of technical efficiency revealed that framers on soil group no 22 exhibited lower technical efficiency level than famers on soil group no 17 by 6.01 percent. This revealed that farmers on soil group no 17 used factors of production more efficiently than farmers on soil group no 22. This group of farmers should be the target for implement developing intensive extension services. Further research is required in-depth interview from best practices reference group for analysis what is characteristic system and how to have high technical efficiency.