BACKGROUND Preeclampsia involves an inflammatory response and vascular endothelial dysfunction. In COVID-19, there is also tissue damage and an inflammatory response that stimulates the formation of D-dimers and an increase in the neutrophil-to-lymphocyte ratio (NLR). These 2 parameters have become laboratory tests carried out both in preeclampsia and COVID-19. This study aimed to determine the relationship between D-dimer levels and NLR in patients with both COVID-19 and preeclampsia. MATERIAL AND METHODS This was an observational analytic study with a retrospective approach. The subjects were pregnant women with gestational age >20 weeks diagnosed with severe preeclampsia and had D-dimer and neutrophil-to-lymphocyte ratio (NLR) laboratory results at Hasan Sadikin Hospital Bandung during the period April 2020 to July 2021. We enrolled 31 COVID-19 patients with preeclampsia and 113 COVID-19 patients without preeclampsia. RESULTS The mean level of D-dimer in COVID-19 patients with preeclampsia was 3.66±3.15 and in those with COVID-19 without preeclampsia it was 3.03±3.15 (P<0.05). The mean NLR value in COVID-19 patients with preeclampsia was 7.22±4.30 and in COVID-19 patients without preeclampsia it was 5.47±2.20 (p<0.05). In the Spearman correlation test, the correlation coefficient was 0.159. Area under curve (AUC) D-dimer level was 64.9% (p<0.05) and NLR was 61.7% (p<0.05). CONCLUSIONS There was a significant difference (P<0.05) in D-dimer and NLR between COVID-19 patients with preeclampsia and those without preeclampsia. There was also a weak positive relationship between D-dimer and NLR levels in COVID-19 patients with preeclampsia, which means that the higher the D-dimer level, the higher the NLR value in COVID-19 patients with preeclampsia.