In today’s society adolescents are exposed to several forms of social medias on a daily basis. Social media has grown to be the most prominent source of health-related materials. For example, the use of social media, and foremost the interaction with health-related content, can contribute to develop a negative body image and mental health. Body and health are a crucial part of the Physical Education course in Swedish Upper Secondary School. Therefore, it is meaningful to investigate how social media impact Upper Secondary School students’ body image and also their attitude towards physical education. The students’ levels of social media usage can therefore have an impact on their body image and, by extension, on their attitude towards physical education. The aim of this study is to establish if there is a relationship between level of social media usage, body image and attitude towards physical education. Inorder to investigate these relationships, body image will function as a form of mediator. The method used in this study was a digital questionnaire that was taken by 197 students in Upper Secondary School. The result showed that there was a significant correlation between a high level of social media usage and a negative body image. The result also showed that there is a significant correlation between a positive body image and a positive attitude toward physical education. Finally, the result showed that there was no explicit relationship between social media usage and attitude towards physical education. Therefore, it is vital for physical education teachers in Swedish Upper Secondary School to actively strive towards that the education will not contribute to enhance the students negative body image.