Purpose: This study aimed to assess medical students’ presence on Facebook and the extent of their visible activity, with particular reference to online professionalism. Methods: This was a cross-sectional study including all medical students enrolled in the University College of Medical Sciences, University of Delhi, India during the period of the study, which was conducted from 2011 to 2012. After approval by the Institutional Ethical Committee, the full names of all students were obtained from our institution. After creating a fictitious profile, Facebook was searched for students’ profiles, and those found were examined for visible content and unprofessional behaviour. Results: Of 611 students, 477 (78.1%) had detectable Facebook profiles. Out of 477 profiles, date of birth, address, email, phone number, religion, and political views were rarely shared; sexual orientation and relationship status were displayed on approximately one third of the profiles; and an identifiable profile picture (80.3%), field of study (51.6%), and institution (86.2%) were commonly shared . The visible content included friend lists (88.7%), photo albums (36.1%), and associations with diverse groups and pages (97.1%). Five profiles (1.05%) displayed unprofessional content, including one profile photograph depicting alcohol consumption, one association with groups relating to excessive alcohol consumption, two profiles containing sexually explicit language, and one association with a sexist page. Conclusion: Most of our students use Facebook’s privacy settings to hide some content from others. Unprofessional content was rarely visible from a stranger’s profile. However, even when hidden from strangers, unprofessional behaviour is still unprofessional behaviour. As Facebook is an integral part of life, it is important for medical educators and students to understand the implications and importance of e-professionalism. Professionalism curricula should address e-professionalism.