Objective To analyze the characteristics of health information needs among enterostomy patients within online question-and-answer (Q&A) communities, providing a scientific basis for developing personalized health education and nursing intervention strategies. Methods Web crawler technology was employed to retrieve data related to enterostomies from online Q&A communities. The Latent Dirichlet Allocation (LDA) topic model was utilized to extract latent themes, which were subsequently categorized based on the Existence-Relatedness-Growth (ERG) theory. Results A total of 17,449 valid text entries were included, from which 11 distinct themes were identified. Existence needs accounted for 42.35% of the data, primarily involving complication prevention, long-term health management, basic stoma care, symptom recognition and management, and postoperative dietary nursing. Relatedness needs represented 36.07%, including medical team support, family and social support, disease cognition and communication, and disease understanding and acceptance. Growth needs comprised 21.58%, covering postoperative identity reconstruction and the sharing of experiences and feedback. Conclusion The health information needs of patients are characterized by the co-existence of existence, relatedness, and growth dimensions. Nursing professionals should monitor shifts in patient requirements, ensuring that while explicit existence needs are met, support and guidance for relatedness and growth needs are also prioritized to enhance patients′ quality of life and self-management capabilities.