The paposeses of this research were 1) to study the happiness level of Mahachulalongkornrajavidyalaya University Vietnamese students, Wang Noi, Ayuthaya, Thailand, 2) to compare the happiness of Mahachulalongkornrajavidyalaya University Vietnamese students, Wang Noi, Ayuthaya, Thailand, 3) to To receive suggestions from Vietnamese students, to make student life happier and sustainable development of Mahachulalongkorn University.

The research methodology consists of research design which is a mixed method; namely qualitative and quantitative study. The research tools are questionnaires and in-depth interviews. For the population, there are 90 Vietnamese students who are study from the Mahachulalongkornrajavidyalaya University. (OR) The sample was selected from 90 students. The SPSS systems was used for data analysis. The tool used for collecting data is questionnaire. The statistics used for analyzing descriptive data are percentage, mean T-test and f-test for Hypothesis testing.

            1. The Vietnamese students studying at Mahachulalongkornrajavidyalaya University. Overall have Level that moderate a large scale average of 2.90 and a standard deviation of 0.56 When considering each aspect it was found that. Positive feelings of happiness. Level of moderate on a scale average of 3.30 and a standard deviation of 0.67. Expectations and expected success. Level of high on a scale average of 3.39 and a standard deviation of 0.65. Coping skills. Level of moderate on a scale average of 3.09 and a standard deviation of 0.60. Valuable life experiences for the soul. Level of moderate on a scale average of 3.05 and a standard deviation of 0.60. Family support. Level of moderate on a scale average of 3.37 and a standard deviation of 0.60. Support from your friends. Level of moderate on a scale average of 3.38 and a standard deviation of 0.55. Control of one's ownmind. Level of low on a scale average of 2.09 and a standard deviation of 0.48. Perception of health status. Level of low on a scale average of 2.44 and a standard deviation of 0.57. Negative feelings of happiness. Level of low on a scale average of 1.99 and a standard deviation of 0.35.

            2. The personal factor that consists of age of Vietnamese students, and when the F-test was used to test for differences from the mean, it was found that there was a statistically significant difference at 0.05. This shows that the factor of age affects the happiness of Vietnamese students and differences were analyzed using Scheffe statistics. Fount that Vietnamese Students are under 25 years old. Difference, the students are Between 31-35 years old. Personal factors other than that do not influence the happiness of Vietnamese students.

            3. Vietnamese students find happiness in the opportunity to study at Mahachulalongkornrajavidyalaya University. The expectations of Education success. The opportunity to study English and Buddhism. The chance to exchange experiences with international friends. And supporting from family and university benefits.