INTRODUCTION: Anticoagulant treatment approach in patients with COVID-19 is not well studied and not standardized. We aimed to compare the effects of standard prophylactic and pre-emptive therapeutic Low-Molecular-weight Heparin (LMWH) treatment approaches on mortality in patients with COVID-19. PATIENTS AND METHODS: This retrospective and single-centre study includes patients aged ≥ 18 years, who were diagnosed with COVID-19 and treated with LMWH during the hospital stay. Therapeutic dose of LMWH was defi ned as 1 mg/kg subcutaneously twice daily and prophylactic dose of LMWH was defi ned as 40 mg subcutaneously once daily. RESULTS: Among the 336 patients diagnosed with COVID-19 pneumonia, 115 patients, who received LMWH were included in the study. The mean age was 58.6 ± 13.3 and 58 (50.4 %) of the patients were male. Sixty-nine (60 %) of the patients were treated with prophylactic and 46 (40 %) therapeutic LMWH. In-hospital mortality was not different between patients treated therapeutic LMWH and prophylactic LMWH by the multivariate regression analysis (OR=2.187, 95% CI 0.484-9.880, p=0.309) and the propensity score modelling (OR=1.586, 95% CI 0.400-6.289, p=0.512.) CONCLUSION: Clinicians should consider the potential risks and benefi ts of standard prophylactic and pre-emptive therapeutic LMWH. Therefore, anticoagulant therapy should be individualized in patients with