Background <p>Metabolic and bariatric surgery is the most effective obesity treatment, and it has been demonstrated that an individual’s preoperative impulsivity can modulate the effects of MBS. However, it remains unclear whether MBS subsequently alters impulsive personality traits and impulsive decision-making.</p> Methods <p>A total of 66 MBS candidates were followed for 24 months after surgery. Impulsive decision-making and impulsive personality were assessed using the Delay Discounting Task and the Barratt Impulsiveness Scale, respectively. A mixed linear model incorporating anxiety and depression levels was applied to examine postoperative changes across each three-month postoperative period (quarter).</p> Results <p>Patients with obesity showed a significant reduction in impulsive personality after surgery, reaching a level comparable to that of healthy controls within the first three months. Impulsive decision-making also improved substantially following surgery. While reductions in depression and anxiety contributed meaningfully to improvements in impulsive personality, they did not exert a significant influence on impulsive decision-making.</p> Conclusion <p>Both impulsive personality and impulsive decision-making improved significantly following MBS. Impulsive personality declined to a level similar to healthy individuals within the first three months, and improvements in depression and anxiety further facilitated this reduction. These findings highlight the clinical relevance of monitoring impulsivity and emotional symptoms after surgery, as such improvements may enhance postoperative behavioral adherence and long-term weight-management outcomes.</p>