INTRODUCTION: The incidence of inflammatory bowel disease (IBD) has been increasing, with adolescents and young adults being the peak age of onset. Self-management behaviors were demonstrated to enhance remission and quality of life, yet the mechanisms influencing self-management behaviors remained under-explored. Perceived social support is crucial to self-management behaviors, alongside the roles of basic psychological needs, anxiety, and depression. METHODS: We conducted a two-center cross-sectional survey in China from July to August 2024 via convenience and snowball sampling to investigate how these variables influence self-management behaviors. Data were collected utilizing the structured self-report questionnaires. Mediating effects were analyzed using the bootstrap method. RESULTS: A total of 183 adolescents and young adults with IBD (male: 71.58%), aged 13 to 24 years old ( CONCLUSION: Clinical practitioners should enhance social support for adolescents and young adults with IBD and improve their perceptions of such support, fulfill basic psychological needs, and alleviate anxiety and depression to promote effective self-management behaviors.