Adolescent striae are more common in girls. The striae in boys can be misinterpreted as a result of non-accidental injuries such as physical abuses and violence. We reported a case of a 16-year-old boy who presented with multiple linear purplish striae on the upper trunk and both axillae area. The skin lesion was initially interpreted as lesions resulted from physical abuse and bully activities at his school. The parent was concerned about the skin lesions and they thought their son had been assaulted at school. The diagnosis of physiological striae in adolescence was made after excluding other endocrine disorders and related diseases. Further assessment revealed there was no history of recent physical assaulted at his school. This case illustrates that the unfamiliarity with this skin condition can be resulted in misinterpretation of the cases. However, suspiciousness for non-accidental injury is crucial, especially among adolescent groups who are at risk to be involved in the bully activities. The misinterpreted of the adolescent striae may cause stress to the parent or other family members and it has sometimes led to the unnecessary legal acts which might be taken by the protective parent.