BackgroundCoronavirus disease 2019 (COVID-19) is a global pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2). It has been found that coronary artery disease (CAD) is a comorbid condition for COVID-19. As the risk factors of CAD, whether blood lipids levels are causally related to increasing susceptibility and severity of COVID-19 is still unknown.ObjectiveWe aim to measure the causal effects between blood lipids and COVID-19 using two-sample Mendelian Randomization (MR) methods.MethodsWe performed two-sample MR analyses to explore whether dyslipidemia, low density lipoprotein cholesterol (LDL-c), high density lipoprotein cholesterol (HDL-c), triglyceride (TG) and total cholesterol (TC) were causally related to COVID-19 risk and severity. The GWAS summary data of blood lipids involving in 312571 individuals and dyslipidemia in a total of 53991 individuals were used as exposures, respectively. Two COVID-19 GWASs including 1221 infected patients and 1610 severe patients defined as respiratory failure were employed as outcomes. ResultsThe MR results showed that dyslipidemia was casually associated with the susceptibility of COVID-19 and induced 27% higher odds for COVID-19 infection (MR-IVW OR = 1.27, 95% CI: 1.08 to 1.49, p-value = 3·18 × 10-3). For blood lipids, the increasing level of TC will raise 18 % higher odds for the susceptibility of COVID-19 (MR-IVW OR = 1.18, 95% CI: 1.06 to 1.31, p-value = 3.08 × 10-3). Based on MR estimates, we further carried out gene-based analysis and found that ABO gene was associated with TC.Conclusions Dyslipidemia is casually associated with the susceptibility of COVID-19 and the blood TC level is a risk factor for the susceptibility of COVID-19. In addition, the different susceptibility of COVID-19 in specific blood group may be partly explained by the TC concentration in diverse ABO blood groups.