Abstract: Online Social networks have gained a tremendous popularity among people all around the world, especially university students. As social media site is a vital part in today’s university students, it has also a negative impact. The objective of this study was to assess the impact of social media on the academic achievement of female students at Jimma University. To achieve this objective, the researchers employ descriptive research design that consider survey methods and partly exploratory research design. 493 female students were randomly selected based on their Grade point Average by categorizing (1.75-2:00, 2.00-3.00 and 3.00-4.00). A questionnaire was distributed among 493 female students at colleges and institutes of the university in order to explore the influence of social media on their academic performance. Grade point averages of these students were also reviewed from the registrar to identify the impact of social media on their academic performance. The Collected data was analyzed and presented in terms of frequency, percentage, and mean score of statements by using SPSS version 20.0 software. Correlation was also done to show the relationship between Social Media Network usage rate and the variables of Grade Point Average.