Monasteries, temples and viharas are not only religious buildings for practicing monkish activities but they are also tourism resources that reflect rural way of life and civilization. They are sources of history, education, art and architecture, including they link cultural backgrounds to communities and the settlement of communities. Thus, touring important monasteries, temples and viharas is a type of tourism which is very popular. This is consistent with a general Thai belief that paying homage to sacred places, making merit or giving alms will lead practitioners to auspicious things and happiness. The purposes of this research were to investigate: 1) the backgrounds of religious buildings and ground of cultural tourist sites in the Mekhong Basin area, 2) current situations and difficulties of religious buildings and ground of tourist sites in the Mekhong Basin area, and 3) the ways to improve strategic development of cultural tourist sites in the Mekhong Basin area. Research areas were these: 1) Nakhon Phanom Province consisted of Okat Sri Buaban Monastery, Nak Bun Unna Monastery, Mueang District, and Phra That Phanom Monastery, That Phanom District; 2) Mukdahan Province consisted of Sri Mongkhon Tai Monastery, Mueang District, Phu Dan Tae Monastey, Nikhom Kham Soi, Distrtic, and Song Khon Monastery, Wan Yai District; and 3) Amnat Charoen Province consisted of Tham Saeng Phet Monastery, Mueang District, Phra Lao Thep Nimit, Phana District, and Luang Pu Khao Analayo Vihara, Hua Ta Phan District. The findings have revealed that religious buildings and ground where are culture tourist sites in the Mekhong Basin area consist of monasteries, temples and viharas reflecting national civilization and technology. They are retrospective learning sources of history, archaeology, culture, arts and architecture, including some of them housed with many types of valued things such as cultures, archaeological objects, murals or inscriptions of several fields of knowledge. Some have the advantages of their locations consisted of rivers, trees, woods and excellent natural surroundings. Moreover, some housed with sacred Buddha images for allowing tourists pay homage to them in case they want to receive auspicious things and morale. Current situations and difficulties are a lack of infrastructure-improving, a lack of knowledge on tourism of persons concerned, a lack of community participation in tourism management, a lack of support from organizations concerned, and a lack of public relations. Furthermore, the main difficulty is a lack of coordination between state organizations and private organizations in tourism affairs. The way to develop strategic development of tourist sites are to establish the coordination among organizations and communities in order to solve all difficulties concerning cultural tourist sites and to persuade all organizations and communities concerned in the Mekhong Basin area to coordinate in developing cultural tourist sites, touring routes, tourist information and infrastructures. Both Thai and Lao governments should coordinate in promoting Thai- Lao cultural tourist sites in a form of a tourism network or the Thai-Lao twin cities for tourism. ? EuroJournals Publishing, Inc. 2012.