The purposes of this research were : 1) to study the teaching problems in schools of the Graduate Diploma Certification Students, 2) to compare student’s teaching problems whose sex, original affiliation, and teaching experiences were different, and 3) to collect guidelines of solving teaching problems in schools of graduate diploma students year B.E. 2560. The samples of this study were 123 students derived from Krejcie and Morgan followed by simple random sampling from the population of 180 grad diploma students. A 5-level rating scale questionnaires with the IOC between .67-1.0, and a Cronback’s α-Coeffiecient of .91 were used to collect the data. Statistics used were percentage (%), mean (x ̅), standard deviation (S.D.), t-test (independent) and F-test (One-way ANOVA). Descriptive analysis were also used for guidelines of solving the teaching problems. The major findings were : 1. As a whole, the teaching problems of the Graduate Diploma Certification Students were rated at “less” level. When the problems were analysed seperatedly, they were also rated at “less” level-ranking from high to low were administrative problems, student themselves students as teachers, and supportive personnel, problems. 2. When comparisons of the teaching problems were taken into consideration, it was found that, as a wholes, their teaching problems were not statistically different. When the teaching problems regarding student themselves, supportive personnel, and administrative problems were analysed separately. Significant differences were not found regardless of sex, original affiliations, nor teaching experiences. 3. Guidelines in solving teaching problems were also collected. It was therefor suggested that all who were concerned, i.e., administrative staffs, supportive personnels, as well as students themselves as teachers cooperatively work to solve the problems.