Abstract: This study explored how well perceived adequacy of coursework and practicum context factors (Job comfort, mentoring support, and workload) explained student teachers’ efficacy. Data was collected via a survey questionnaire administered face-to-face to all student teachers (N = 97, or 90%) who engaged in a practicum at secondary schools (grades 9 & 10) in south-west Ethiopia during 2013 academic year. The multiple linear regression analysis revealed a moderate fit model (R2 =0.335), in which 33.5% of the variance in teacher efficacy was attributed to the predictor variables considered in this study (F8, 66 =4.164, P<0.001). Perceived coursework adequacy (β=.420) followed by job comfort (β=.366) remained stronger and positive predictors of student teachers’ efficacy. On the other hand, student teachers’ efficacy was related to sex and placement site, where females and those placed at Gambella site were predicted to be less efficacious, indicating further area of concern to address the observed gap.