In the previous paragraph, the researcher presented the objectives and the importance of the study. In this chapter, reviews of related concepts have been organized into seven parts as follows: First motivation and foreign language learning, Second motivation of students learning foreign language, Third intrinsic and extrinsic motivation, Fourth intrinsic motivation in learning English as a foreign language, Fifth extrinsic motivation in learning English as a foreign language, Sixth English language learning in Thailand and Seventh private and public schools in Thailand.