The current study aimed to identify the negative effects of using the social network (Facebook) on the students of the secondary level and their differences according to the variables of gender and stream. The sample of the study consisted of (224) secondary students: 91 males and 133 females who were intentionally selected from the secondary schools in AlYarmouk area of Bani Kinana in Northern Jordan. The questionnaire was adopted in the process of data collection. The results showed that the mean of the negative effects of using the Social Network (Facebook) on the secondary students as a whole was (2.98) by a medium degree. The descending order of the fields of the tool is: (Social effects, health effects, academic effects, behavioral effects, and emotional and psychological effects). The results also showed that there were no statistical differences in the negative effects of using the social network (Facebook) on the secondary students due to the impact of the variables of gender and stream. The study recommended the need that the Ministry of Education adopts a national training project to help students cope with the negative effects of using the Facebook.