Singing styles of Thai-Lao ethnic groups are parts of the art of singing which are widely popular with people along both sides of the Mekong River. Singing styles of each ethnic group resulted from creative ideas of local ancestors and they are accepted as a linguistic culture and wisdom heritage which have been perpetuated until now. The purposes of this research aimed at investigating the background of singing styles of Thai-Lao folksingers, the current situations and difficulties of singing styles of Thai-Lao folksingers, and the conservation, perpetuation and development of singing styles of Thai-Lao folksingers along both sides of the Mekong river. Results: 1) the background of singing styles of Thai-Lao folksingers originated from singing styles which were handed down to descendants by ancient folksingers and they have been perpetuated up to now. The intonation of the dialect of each community is different so singing styles are also different. "Lam Si Phan Don" is the most popular singing style of all which folksingers like to present to the audience, it originated from singing style of folksingers who came from the area of thousands islets called "Si Phan Don" in the Mekong River of Champasak, the southern-province of Laos. Generally, this singing style is used for responsive lyrics of men and women, 2) current situations and difficulties of singing style of folksingers have revealed that many folksingers write new songs and use a Lam Si Phan Don-singing style for presenting the audience. The famous folksingers of Laos recorded their songs in a Lan Si Phan Don singing style and with modern background music in the forms of cassettes, CDs and VCDs for commercial distribution. There are many difficulties concerning singing styles of folksingers such as a lack of persons who transmitted them to future generations, a change of the trend of the audience in seeing folk singing-performance and an economic change, thus folksingers must adapt themselves by leading their life carefully. Moreover, it's hard to earn a living as an folksinger because this occupation gives a low income. 3) conserving, perpetuating and developing singing styles of Thai-Lao folksingers along both sides of the Mekong River for creating a cultural value should conduct by encouraging folksingers establish their network in order to help one another, conserving singing styles and performing customs, perpetuating them through educational institutes, transmitting them to the youth, developing performing elements to the audience attraction and developing the quality of artists, including developing the cooperation of organizations concerned. © EuroJournals Publishing, Inc. 2011.