This article aims to study the problem of political finance in Thailand. The Article is divided into two parts. The First dealt with political parties and political finance before 1997, while the second concentrates on political finance under the 1997 Constitution. From 1932 until now, political parties in Thailand have gone through an uneven process of democratization. Some academics label Thai political parties as election parties. This phenomenon has led to rampant corruption and vote buying practices. It is evident that political finance and expenditure are at the root of the problem. Therefore, a desire to eliminate vote buying and corruption leaded to the promulgation of the new constitution 1997. The Charter adopted a variety of measures, for example, compulsory voting, a mixed electoral system and an independent Election Commission. And in order to cope with the problem of transparency in political finance, the new constitution provides various improvements; regulation of donations, provision of public funding for parties and candidates, limits on campaign expenditures and, more importantly, transparency in political financing. As for disclosure and transparent of political finance, the Thai system is comparatively good. But the problem concerning regulation of political finance how to regulate, and how to make that regulation accepted by political actors.