Endothelial progenitor cell (EPC) recruitment and angiogenesis play crucial roles in aneurysm neck endothelialization, but the mechanisms of EPC recruitment and angiogenesis are still unclear. Recent studies have shown that long noncoding RNAs (lncRNAs) can regulate the function and differentiation of cells in various ways. LncRNA TUG1 is involved in liver cancer and glioma-mediated angiogenesis. The aim of this study was to investigate the role of lncRNA TUG1 in regulating EPC migration and differentiation. Overexpression and knockdown of lncRNA TUG1 with lentivirus, scratch assays, Transwell assays and tube formation assays using EPCs isolated from rat bone marrow showed that lncRNA TUG1 overexpression promoted EPC migration, invasion and differentiation. Moreover, ELISAs showed that lncRNA TUG1 overexpression increased VEGF expression. Bioinformatics prediction, luciferase assays, Western blots and RIP assays indicated that lncRNA TUG1 functions as a ceRNA (competing endogenous RNA) for miR-6321 and that miR-6321 inhibits EPC migration and differentiation through its target, ATF2. As a potential therapeutic target, lncRNA TUG1 may play a vital role in the pathogenesis of aneurysms.