Identifying eating behaviors associated with suboptimal weight loss following bariatric surgery remains important. This study assessed the relationship between eating behaviors and weight loss following bariatric surgery in a racially diverse sample. Participants were assessed before surgery and 6 and 12months postoperatively, with the Structured Clinical Interview for DSM-5, the Eating Disorder Examination-Bariatric Surgery Version, and validated measures assessing a range of eating behaviors. Linear mixed effect models were used to test the impact of eating behaviors on percent weight loss (%WL) at 6 and 12months. We enrolled 300 participants (mean age 40.1years; BMI 45.9kg/m2; 87% women; 62% Black and 30% White). The majority (82%) underwent sleeve gastrectomy (SG). Mean %WL was 23.0 ± 5.1% at 6months and 26.2 ± 7.6% at 12months. Subjective binge episodes prior to surgery predicted greater %WL over the first 12 postoperative months (p = 0.028). Postoperative disinhibition, hunger, night eating symptoms, objective binge episodes, global disordered eating attitudes and behaviors, and snacks per day were associated with smaller %WL over 12months (all p's < 0.01). The presence of picking/nibbling and addictive-like eating behaviors was not associated with %WL at the end of the first postoperative year. Among a diverse participant sample, problematic eating behaviors following surgery were associated with smaller %WL over 12months. Postoperative assessment and treatment of eating behaviors are needed to address these issues as they arise and to prevent attenuation of early weight loss in some patients.