Pendahuluan: Penggunaan smartphone yang tinggi di kalangan mahasiswa berpotensi memengaruhi ritme sirkadian melalui paparan cahaya biru dan perubahan perilaku tidur. Gangguan ritme sirkadian dapat tercermin pada perubahan chronotype, yaitu preferensi biologis terhadap waktu tidur dan aktivitas. Penelitian mengenai hubungan durasi screen time dan chronotype di Indonesia masih terbatas. Penelitian ini bertujuan untuk menganalisis hubungan antara durasi screen time smartphone dengan chronotype pada mahasiswa Fakultas Kesehatan Masyarakat Universitas Indonesia tahun 2025. Metode: Studi ini menggunakan desain cross-sectional pada mahasiswa aktif jenjang S1 FKM UI tahun 2025. Data dikumpulkan melalui kuesioner elektronik menggunakan Self-Reported Smartphone Usage Questionnaire (SSUQ) untuk mengukur durasi screen time dan Reduced Morningness–Eveningness Questionnaire (rMEQ) untuk menentukan chronotype. Analisis dilakukan secara univariat, bivariat, dan multivariat menggunakan regresi logistik multinomial dengan pengendalian variabel perancu. Hasil: Sebagian besar mahasiswa memiliki durasi screen time smartphone yang tinggi (>4 jam per hari). Chronotype tipe menengah merupakan jenis yang paling banyak ditemukan, diikuti tipe malam dan tipe pagi. Hasil analisis multivariat menunjukkan bahwa mahasiswa dengan durasi screen time smartphone tinggi memiliki kecenderungan lebih besar untuk memiliki chronotype tipe pagi setelah dikontrol oleh variabel perancu. Kesimpulan: Terdapat hubungan antara durasi screen time smartphone dengan chronotype pada mahasiswa FKM UI. Durasi screen time yang tinggi berhubungan dengan kecenderungan chronotype tipe pagi. Hasil penelitian ini diharapkan dapat menjadi dasar pengembangan program promosi kesehatan terkait manajemen screen time dan kesehatan tidur di lingkungan perguruan tinggi.

Introduction: High smartphone use among university students may affect circadian rhythms through blue light exposure and changes in sleep-related behaviors. Disruption of circadian rhythms can be reflected in alterations of chronotype, defined as an individual’s biological preference for sleep and activity timing. Research examining the relationship between screen time duration and chronotype in Indonesia remains limited. This study aimed to analyze the association between smartphone screen time duration and chronotype among students of the Faculty of Public Health, Universitas Indonesia, in 2025.  Methods: This study employed a cross-sectional design involving active undergraduate students of the Faculty of Public Health, Universitas Indonesia, in 2025. Data were collected through an electronic questionnaire using the Self-Reported Smartphone Usage Questionnaire (SSUQ) to measure screen time duration and the Reduced Morningness–Eveningness Questionnaire (rMEQ) to determine chronotype. Data were analyzed using univariate, bivariate, and multivariate analyses. Multinomial logistic regression was applied to assess the association between smartphone screen time duration and chronotype while controlling for potential confounding variables. Result: Most students reported high smartphone screen time (>4 hours per day). The intermediate chronotype was the most prevalent, followed by evening and morning types. Multivariate analysis showed that students with high smartphone screen time had a greater tendency to exhibit a morning-type chronotype after adjusting for confounding variables.  Conclusion: There was an association between smartphone screen time duration and chronotype among students of the Faculty of Public Health, Universitas Indonesia. High smartphone screen time was associated with a greater likelihood of morning-type chronotype. These findings may inform the development of health promotion programs focusing on screen time management and sleep health in university settings.