The purpose of this research are to investigate 1) personal factors of students majoring in Hotel and Tourism at Santirat Vocational College. 2) The students’ knowledge of trans fatty acids. 3) The students’ consumption behavior of trans fatty acids. 4) The relationship between the personal factors (gender age education average monthly income of students) and their knowledge of trans fatty acids. 5) The differences of consumption behavior among gender age education and average monthly income of students. The samples are 254 of vocational students. The questionnaire was used to collect the data. The statistics used to analyze data in this research were frequency percentage Mean Standard Deviation Chi-Square (χ2) t-test and ANOVA. The data was analyzed by statistical tools. It was found that most students knew very little about trans fatty acids. They sometimes consumed food with trans fatty acids. The finding also found that there were a relationship between knowledge of trans fatty acids and personal factors; gender age education and average monthly income of students with statistically significant level at .05. It was also found that different gender had different consumption behavior whereas age education average income of students were not different with statistically significant level at .05.