This study was conducted to explore the major constraints encountered in teaching Englishrnlanguage in-group work at Adea Model Secondary School, particularly in grade 9. To achieve thernobjectives, descriptive study was employed. Data were gathered from 180 students, 10.2% ofrnthe total population in four randomly selected classrooms, and ten English language teachersrnthrough three instruments (observation, questionnaire and interview). The data collectedrnthrough the questionnaire were analyzed using descriptive statistics (frequency andrnpercentage). But those gathered through classroom observations, semi-structured interview andrnopen ended questions were analyzed qualitatively.rnThe results of the study revealed that both students and teachers perceive group workrnpositively. However, the followings were found to be the main constraints encountered duringrngroup work activities: since students were not given orientations about their roles in- grouprnwork, they did not play their expected roles, some students came with poor educationalrnbackground and low language proficiency ; as a result, they intended to use their L1 or theyrnbecome careless to take part in activities, group activities were conducted intermittently andrnthe time given for group work was not sufficient , there was no group leader and secretary inrneach group and the formed groups last only for a period, some students lack experience ofrnworking in groups; some were passive for the activities were not graded , in some activernlearners used to dominate the group; because of fear or lack of self confidence some studentsrnfailed to take part in group work.rnIn addition, teachers did not: use group work activities regularly; determine the number ofrnstudents in a group, give sufficient time for group work activities, allow students to report,rncomment and criticize the tasks; monitor while students perform activities ; provide feedbackrnand grade group work activities at the end of the tasks. Finally, teachers were noticed givingrnmore emphasis for grammar than group work. As to the situation of learning classrooms, those,rnwhich were made of iron sheets, were not totally suitable to stay in, so the above constraintsrnhamper the normal classroom interaction.rnTherefore, possible recommendations were forwarded for the concerned bodies to alleviate thernexisting problems proved by the study.