The main purpose of the study was to assess the effect of cell phones on student academicrnperformance. The study was conducted in Chole Secondary Schools of Arsi Zone in OromiarnRegion. Stratified random sampling method was used to select the respondents of the study. Amongrnthe total of 1502 students enrolled in grades 9 and 10 during 2017/18 academic year, 75% of themrnwere imagined to have mobile phone (1127 students). To select the required sample size (301)rnfrom 1127 target Chole Secondary School students enrolled in 2017/18 academic year, simplernrandom sampling technique was employed. The quantitative data was gathered by the help ofrnquestionnaire from students and was analyzed by descriptive statistics that consist of percentage,rnmean and inferential by Pearson chi square test. The qualitative data gathered from interview wasrnanalyzed using narrative methods. Survey findings show that the negative perceived effect ofrnmobile phone on academic performance is concerned, thorough analysis of the survey datarnrevealed that to the average 34.12% of the students acknowledged that their mobile phone affectrnnegatively their academic performance as 23.64 % affected positively. In other words, chi-squarernstatistics revealed that level of mobile utilization have statistically significant association with thernaverage grade score of students at less than 0.05. This implies that excessive mobile utilizationsrnhave significantly negative impact on the academic performance of secondary school students letrnalone the other things remain constant. Finally, the researcher likes to recommend that thernmajority of sample students are under â€œweakâ€ of studentsâ€™ academic achievement and too smallrnnumber of sample students (3%) was among â€œexcellentâ€ group of studentsâ€™ academic achievement.rnTo curve the situation, the responsible bodies had better to be in a better position of helpingrnstudents so as to improve their academic performance.