Nowadays, social media are dominating the life of people. Facebook has become noticeably widespread among the youth, and students in particular. Research has indicated that Facebook could be an effective platform for language learning. This study, therefore, comes to explore the effects of Facebook-assisted teaching on learning English for specific purposes by students at the University of Tabuk, Saudi Arabia. A sample of 64 students from the Faculty of Business Administration, taking a Business Letters course in English, were divided into a Facebook-tutored group and a traditional classroom tutored group and were given the same vocabulary content. The two groups were given pre- and post-tests to measure their vocabulary learning, and were subjected to an interview to gauge their attitudes towards the instructional methods which were put to use. However, no significant difference between the two groups was found in terms of achievement in spite of the positive response and the high satisfaction level the Facebook-tutored students showed towards the use of such a platform.