The explosion of social networking websites in general, and Facebook in particular, impacts the educational context both positively and negatively. Too much time spent on Facebook leads to negative effects on the university work of students. The objectives of this research are to measure and analyse the relationship between the Facebook dependence and the negative consequences of the excessive use of Facebook on the university work of students. In this respect, a conceptual model has been tested that has two inter-correlated latent variables: the withdrawal syndrome, measuring the Facebook dependence and the negative consequences onto the university work. The analysis of results has been done onto three groups featuring the user’s profile according to the network size (number of Facebook friends) of students. The findings show that the larger the Facebook network, the higher the frequency and duration of Facebook use. The analysis of measurement invariance shows that the model exhibits factorial, metric, and scalar invariance on the three user profiles. The comparison between groups shows that students having larger networks and spending more time on Facebook have a higher level of dependence and their university work is more affected.