The purpose of this study was to examine the state of Post Graduate Diploma in Teaching trainees’ self-efficacy belief and the factors that contributed to its development with emphasis to Dilla University. To this end, 112 trainees were selected using stratified random sampling technique, and data was collected through questionnaire which was analyzed using independent sample t-test, one sample t-test, and Multiple Linear Regression. The findings indicated that trainees have marginally average level of efficacy. It was also found that attitude to teaching (β= .573, t=10.129, p<.05) was the biggest contributor to self-efficacy belief followed by teachers’ professional collaboration in secondary schools (β= .198, t= 5.276, p<.05) and in-campus training practice (β= .146, t=3.201, p<.05) respectively. In contrast to popular expectations, the study additionally revealed that there was no significant mean difference in trainees’ efficacy scores in terms of their Cumulative Grade Point Average. Based on these major findings, it was concluded that trainees’ efficacy with regard to bringing desired impact on secondary school students’ achievement and behavior was not adequate and requires immediate attention. Finally, it was recommended that graduates should be given on-job training and teachers’ professional collaboration in Ethiopian secondary schools should be further strengthened.

Keywords: Post Graduate Diploma in Teaching (PGDT), Attitude, Teacher self-efficacy.