Objective. To investigate the association between HLA susceptibility and disease severity markers and the extent of atherosclerosis in patients with psoriatic disease. Methods. White patients with psoriatic arthritis (PsA) and psoriasis without PsA (PsC) were recruited. An ultrasound of the carotid arteries was performed and the size of each atherosclerotic plaque was measured. The resulting score, the total plaque area (TPA), represented the extent of atherosclerosis. HLA genotyping was performed using sequence-specific oligonucleotide probes. The association between 10 HLA susceptibility and severity markers of PsC and PsA and the severity of atherosclerosis was assessed by ordinal logistic regression models adjusted for age, sex, and cardiovascular (CV) risk factors. Results. The study involved 411 patients (273 PsA, 138 PsC). Of them, 61.8% had at least 1 atherosclerotic plaque. HLA-B*13:02 and HLA-C*06:02 were associated with more severe atherosclerosis (age-and sex-adjusted OR 2.31, 95% CI 1.23-4.32 and OR 1.68, 95% CI 1.12-2.52, respectively). HLA-B*38:01 was associated with less severe atherosclerosis (OR 0.49, 95% CI 0.28-0.86). These associations remained statistically significant after adjusting for CV risk factors. Higher levels of erythrocyte sedimentation rate (ESR) were associated with more severe atherosclerosis (age-and sex-adjusted OR 1.33, p = 0.02). HLA-B*13:02-positive (p = 0.01) as well as HLA-C*06:02-positive (p = 0.008) patients had higher levels of ESR over time. Conclusion. HLA-C*06:02 and B*13:02 alleles are associated with a higher burden of atherosclerosis in patients with psoriatic disease. This association may be mediated by a higher level of systemic inflammation.