The aim of this study was to explore the experiences and sources of stress among practicing student-teachers in the Eastern region of Ethiopia. A total of 112 participants were selected from the total population of 197 using stratified random sampling technique. Data were collected using the Perceived Stress Scale (PSS), sources of stress measure and socio demographic characteristics of participants. To supplement the survey results, four groups of focus group discussions were conducted. The result indicated that 96% of female and 90% of male participants scored a stress level of 29 and above (out of the possible 56) indicating that they were fairly often, or very often, stressed. Though female participants showed higher level of stress than their male counterparts, the difference was not significant. Student misbehavior, inability to contact with significant others like families and relatives, and uncomfortable working environment were identified in that order as the greatest stressors. The implications of the results to teacher training institutes and other stakeholders in the teacher-training programs is discussed.