Background: Aortic regurgitation (AR) is a common cardiovascular complication in patients with Takayasu arteritis (TAK), and complication after aortic valve surgery (AVS) is not rare. This study aimed to identify the long-term postoperative outcomes for significant AR in patients with TAK compared with those in patients without TAK. Methods: We included 35 patients with TAK with moderate-to-severe AR who underwent AVS and compared their postoperative outcomes with those of 105 age- and operation period-matched patients with severe AR but without TAK. The risk factors for poor outcomes (all-cause death and major adverse cardiac and cerebrovascular events [MACCE]) in patients with TAK were analyzed using multivariate Cox regression. Results: The 10-year overall survival rate was 70.5% in patients with TAK and 89.4% in those without TAK (p = 0.048). The MACCE and reoperation rates were significantly higher in patients with TAK (10-year freedom from MACCE, 58.2% vs. 86.4% [p < 0.001]; 10-year freedom from reoperation, 64.5% vs. 98.3% [p < 0.001]). Eighteen of the 35 patients with TAK (51.4%) had poor outcomes, and multivariate analysis revealed that significant coronary artery involvement (hazard ratio [HR], 4.178; 95% confidence interval [CI], 1.222–14.282; p = 0.023) and decreased estimated glomerular filtration rate (HR, 0.968; 95% CI, 0.947–0.989; p = 0.003) were associated with poor outcomes. Conclusion: The long-term postoperative outcomes for AR were poorer in patients with TAK than in those without TAK. The poor outcomes in patients with TAK were associated with coronary artery involvement and decreased renal function.