Latar Belakang: Nyeri punggung bawah (NPB) merupakan penyakit yang umum terjadi di masyarakat dan memiliki prevalensi yang tinggi pada mahasiswa kedokteran. Aktivitas perkuliahan daring selama pandemi Covid-19 mengakibatkan duduk berkepanjangan. Sikap duduk tidak ergonomis untuk durasi duduk yang panjang dapat meningkatkan risiko NPB. Penelitian ini dilakukan karena hanya sedikit penelitian yang mencari hubungan tersebut di era pandemi ini. Tujuan: Mengetahui hubungan antara sikap duduk ergonomis dengan NPB pada mahasiswa preklinik Fakultas Kedokteran Universitas Pelita Harapan selama pandemi Covid-19. Metode: Peneliti menggunakan desain studi kuantitatif potong lintang dengan metode purposive sampling. Subjek yang setuju dari pengisian lembar persetujuan (Informed Consent) akan mengisi kuesioner data demografi, RULA (Rapid Upper Limb Assessment), dan Modified ODI (Oswestry Disability Questionnaire). Data penelitian dikumpulkan dalam software Microsoft Excel dan ditabulasi menggunakan program SPSS 28.0. Uji statistik analisis bivariat hubungan antara sikap duduk ergonomis dengan NPB dilakukan dengan metode Chi-Square. Hasil: Dari penelitian ini, didapatkan angka prevalensi NPB (41,77%) mahasiswa preklinik Fakultas Kedokteran Universitas Pelita Harapan yang relatif tinggi. Mayoritas mahasiswa (68,35%) memiliki sikap duduk tidak ergonomis. Hasil uji statistik analisis bivariat menunjukkan terdapat hubungan yang signifikan antara sikap duduk ergonomis dengan NPB (p=0,004; OR=6,09; 95% CI=[1,842-20,130]). Kesimpulan: Terdapat hubungan yang signifikan antara sikap duduk ergonomis dengan NPB pada mahasiswa preklinik Fakultas Kedokteran Universitas Pelita Harapan selama Pandemi Covid-19. Kata Kunci: Sikap duduk ergonomis, Metode RULA, Nyeri punggung bawah, Mahasiswa Preklinik Kedokteran / Background: Low back pain (LBP) is a common disease in the society and has a high prevalence among medical students. Online university classes during Covid19 pandemic cause prolonged sitting. Non-ergonomic sitting for a long sitting duration could increase the risk of LBP. This study is conducted as only few researchers studied the relationship during this pandemic era. Objective: To understand the relationship between ergonomic sitting and low back pain towards preclinic students of Faculty of Medicine, University of Pelita Harapan, during Covid-19 pandemic. Methods: The author uses quantitative cross-sectional study design and purposive sampling method. Subjects who agreed the informed consent will fill the demographic data questionnaire, RULA (Rapid Upper Limb Assessment), and Modified ODI (Modified Oswestry Disability Questionnaire). Data will then be collected in Microsoft Excel software and tabulated with the SPSS 28.0 program. Statistical bivariate analysis of the relationship between ergonomic sitting and LBP was conducted with the Chi-Square method. Result: From this study, it was found that the LBP prevalence (41.77%) of preclinical students of Faculty of Medicine, University of Pelita Harapan, was relatively high. Majority of students (68,35%) had a non-ergonomic attitude of sitting. Statistical bivariate analysis results show a significant relationship between ergonomic sitting and LBP (p=0,004; OR=6,09; 95% CI=[1,842-20,130]). Conclusion: There is a significant relationship between ergonomic sitting and LBP in preclinical students of Faculty of Medicine, University of Pelita Harapan, during Covid-19 pandemic. Keywords: Ergonomic Sitting, Low Back Pain, RULA Method, Preclinical Medical Student