Abstract Varicose veins of lower extremities (VVs) are a common multifactorial vascular disease. Genetic factors underlying VVs development remain largely unknown. Here we report the first large-scale study of VVs performed on a freely available genetic data of 408,455 European-ancestry individuals. We identified 7 reliably associated loci that explain 10% of the SNP-based heritability, and prioritized the most likely causal genes CASZ1, PPP3R1, EBF1, STIM2 , and HFE . Genetic correlation analysis confirmed known epidemiological associations and found genetic overlap with various traits including fluid intelligence score, educational attainment, smoking, and pain. Finally, we observed causal effects of height, weight, both fat and fat-free mass, and plasma levels of MICB and CD209 proteins.