IMPORTANCE Short-term improvements in sexual functioning are reported after bariatric surgery, but to our knowledge, little is known about the durability of these improvements. OBJECTIVE To determine the percentage of adults with impairment in sexual functioning who experience durable improvements in sexual functioning after bariatric surgery and to identify factors associated with improvements. DESIGN, SETTING, AND PARTICIPANTS The Longitudinal Assessment of Bariatric Surgery-2 is an observational cohort study conducted at 10 hospitals in 6 US clinical centers. Adults undergoing their first bariatric procedure were recruited from 2005 through 2009, data were collected through August 2014. Data analysis was conducted from 2016 to April 2018. INTERVENTIONS Participants completed assessments before the procedure and annually thereafter for 5 years. MAIN OUTCOMES AND MEASURES A self-administered questionnaire was used to assess clinically meaningful differences before and after surgery in past-month sexual satisfaction, desire, and activity and physical health limitations to sexual activity among subgroups who reported sexual functioning at less than domain-specific thresholds before surgery. RESULTS Of 2215 participants eligible for sexual function follow-up, 2036 (91.9%) completed 1 or more follow-up assessment (1431 [64.6%] at year 5), of whom 1607 (78.9%) were women. At the presurgery assessment, median (interquartile range) age was 47 (37-55) years, and the median (interquartile range) body mass index was 45.8 (41.7-51.3). Among those who were not satisfied with their sexual life before surgery (1015 of 1456 women [69.7%]; 304 of 409 men [74.3%]), 56.0% of women (95% CI, 52.5%-59.5%) and 49.2% of men (95% CI, 42.4%-55.9%) experienced clinically meaningful improvements at year 1; these percentages did not significantly differ during further follow-up. Among those who reported physical limitations to sexual activity at baseline (892 of 1490 women [59.9%] and 267 of 406 men [65.8%]), the percentage experiencing improvement in this domain decreased during follow-up, but 73.6% (95% CI, 69.3%-78.0%) of women and 67.6% (95% CI, 59.6%-75.6%) of men continued to report improvements at year 5. Greater postsurgical reduction in depressive symptoms was independently associated with improvement in 4 domains of sexual life among women (frequency of sexual desire: adjusted relative risk [aRR] per 5-point decrease in