Purpose Difficulties in emotion regulation and deficits in interoceptive awareness may be responsible for overeating and weight gain in obesity by increasing the risks of problematic eating behaviors. This study aimed to: (1) examine emotion regulation difficulties and interoceptive deficits in obesity; (2) compare the emotion regulation and interoceptive abilities of moderately and severely obese patients. Methods Participants were recruited through the university, diabetology centers and bariatric surgery departments. A total of 165 participants were categorized in three groups, matched by age and gender, according to their Body Mass Index (BMI). The severely obese (SO), moderately obese (MO) and normal weight (NW) groups were constituted of 55 participants each. Self-report questionnaires were used to assess emotion regulation difficulties (CERQ-DERS) and interoceptive awareness (MAIA-FFMQ). Results Overall, obese participants reported more emotion regulation difficulties and less interoceptive awareness than NW participants did. They also reported a lack of planning strategies and emotional awareness, as well as less ability to observe, notice and trust body sensations. No differences in emotion regulation and interoceptive abilities were found between MO and SO participants. Conclusions Emotion regulation and interoceptive awareness should be targeted in the psychotherapeutic care of obese people, regardless of their BMI. Level of evidence Level III, case-control analytic study.