Background <p>Elevated Lipoprotein(a) Lp(a) levels are associated with coronary atherosclerosis as detected by cardiac computed tomography angiography (CCTA). However, quantitative data including coronary plaque volumes and characteristics are scarce. The current study evaluated the sex-specific correlations between (Lp(a)) levels and the extent and composition of coronary stenosis and plaques.</p> Methods <p>1,946 patients undergoing CCTA (third-generation dual-source scanner) for suspected coronary artery disease were included whose Lp(a) levels were available. Lp(a) values ≥ 125&#xa0;nmol/L were classified as high.</p> Results <p>High Lp(a) levels were observed in 336 patients, who had greater maximum degree of stenosis (49.5 ± 26.4% vs. 43.5 ± 27.6%, <i>P</i> = 0.002), mainly as a result of the pronounced difference in males (53.8 ± 26.0% vs. 46.2 ± 26.8%, <i>P</i> = 0.001). A strong correlation between higher Lp(a) values and high-risk plaque features was noted in the overall cohort (odds ratio [OR]: 1.645; 95% confidence interval [CI]: 1.011 to 2.593; <i>P</i> = 0.037), independent of age and LDL-cholesterol values. In males, high Lp(a) levels were associated with greater total plaque volumes (118.1 [IQR 18.3–284.4] vs. 83.2 [IQR 11.8–226.3] mm³, <i>P</i> = 0.018, Pint = 0.09), including fibrotic components (27.6 [IQR 2.1–109.9] vs. 18.2 [IQR 0.4–65.0] mm³, <i>P</i> = 0.011, Pint = 0.013), whereas in women, only a marginal linear correlation with total plaque volume was observed (19.2 vs. 8.1 mm³; Spearman’s rank correlation R = 0.16, <i>P</i> = 0.037).</p> Conclusions <p>Our study identifies novel sex-specific correlations between Lp(a) levels and coronary plaque characteristics. High Lp(a) levels in men seems to be associated with increased fibrotic plaque volumes and may contribute to greater total plaque burden and high-risk plaque features.</p> Graphical Abstract <p></p>