Cutaneous leukocytoclastic angiitis (CLA) is a condition of clinical interest, with previous studies suggesting an association with herpes virus infections. This study aimed to investigate the causal association relationship between the virus and CLA. Genetic variants linked to the virus were retrieved from the IEU open GWAS project and FinnGen database. Data on CLA were sourced from the FinnGen consortium R7. Mendelian randomization (MR) analysis, including the IVW, MR‐Egger, and weighted median methods, was conducted. Sensitivity analyses were performed to ensure result accuracy. Among the six viruses investigated, only human herpesvirus 6 (HHV-6) demonstrated a causal association with CLA(odds ratio (OR) = 1.886, 95% confidence interval (CI) = 1.053–3.378, p = 0.033), indicating that HHV-6 infection significantly elevates the risk of CLA. Furthermore, both IVW and MR-Egger tests for heterogeneity confirmed homogeneous MR analysis results without evidence of horizontal pleiotropy (p>0.05). No significant causal relationship was observed for other viruses, such as herpes simplex virus (HSV), varicella-zoster virus (VZV), cytomegalovirus (CMV) and Epstein-Barr virus (EBV). Our MR analyses provide strong support for a causal relationship between HHV-6 and CLA, shedding light on the etiology of this condition and highlighting the potential therapeutic implications of targeting HHV-6 in CLA treatment.