Latar Belakang: Sejak tanggal 11 Maret 2020 WHO menyatakan Covid-19 sebagai pandemi. Telah dilakukan upaya pencegahan dengan menjaga jarak minimal dua meter, penggunaan masker dan mencuci tangan dengan sabun dan air atau hand sanitizer. Asrama merupakan area yang rentan dalam penyebaran penyakit menular termasuk Covid-19 karena terdapat banyak orang dari berbagai wilayah yang datang untuk tinggal bersama dalam jangka waktu tertentu. Menurut teori Green, perilaku seseorang dipengaruhi oleh tiga faktor utama, yaitu faktor predisposisi, pemungkin dan penguat. Tujuan: Untuk mengidentifikasi gambaran faktor predisposisi (karakteristik demografi, pengetahuan dan sikap), faktor pemungkin (sumber informasi) dan faktor penguat (dukungan sosial) yang memengaruhi perilaku pencegahan Covid�19 pada mahasiswa di asrama Universitas Swasta di Indonesia bagian Barat. Metode: Penelitian ini menggunakan metode kuantitatif deskriptif. Teknik pengambilan sampel menggunakan purposive sampling. Sampel penelitian adalah mahasiswa di asrama Universitas Swasta di Indonesia bagian Barat berjumlah 181 orang yang dihitung dengan rumus slovin. Hasil: Penelitian menunjukkan 100 (55,2%) mahasiswa memiliki pengetahuan yang baik, sebanyak 93 (51,4%) mahasiswa memiliki sikap baik, sebanyak 107 (58,9%) mahasiswa mendapatkan dukungan sosial dan sebanyak 106 (58,5%) mahasiswa memiliki perilaku yang baik terhadap pencegahan Covid-19. Kesimpulan: Dukungan sosial yang diberikan memengaruhi perilaku pencegahan Covid-19 pada mahasiswa di asrama serta perlu adanya peningkatan pengetahuan dan sikap. / Background: Since March 11, 2020 WHO declared Covid-19 as a pandemic. Prevention efforts have been carried out by maintaining a minimum distance of two meters, using masks and washing hands with soap and water or hand sanitizer. Dormitory is an area that is vulnerable to the spread of infectious diseases including Covid-19 because many people from various regions come to live together for a certain period of time. According to Green's theory, a person's behavior is influenced by three main factors, namely predisposing, supporting and reinforcing factors. Objective: To describe the predisposing factors (demographic characteristics, knowledge and attitudes), supporting factors (sources of information) and reinforcing factors (social support) that influence the Covid-19 prevention behavior in private university dormitory students in Western Indonesia. Methods: This study used a quantitative descriptive method. The sampling technique used is purposive sampling. The sample of this research is private university dormitory students in West Indonesia, totaling 181 people calculated by the slovin formula. Results: The study showed 100 (55.2%) students had good knowledge, as many as 93 (51.4%) students had good attitudes, as many as 107 (58.9%) students received social support and as many as 106 (58.5%) ) Students have good behavior towards the prevention of Covid-19. Conclusion: The social support provided has an effect on Covid-19 prevention behavior in students in dormitories and it is necessary to increase knowledge and attitudes.