Background Understanding the influence of psychosocial factors and symptoms on health-related quality of life (HRQoL) might help researchers develop interventions to optimize HRQoL in patients with neuroendocrine tumors (NETs). Objective The aim of this study was to characterize available evidence on symptoms, psychosocial factors, and HRQoL in patients with NET. Methods For this integrative literature review, the literature search was guided by the methodology proposed by Whittemore and Knafl. MEDLINE, CINAHL, PubMed, PsychINFO, and Google Scholar were searched for articles exploring symptoms, psychosocial factors, and HRQoL in patients living with gastrointestinal NETs. Results Combining keywords yielded 37 articles after removing 2 duplicates. Twenty-three articles were removed because they did not meet inclusion criteria. Two articles had a qualitative design. The final review included 15 studies. Geographically diverse studies indicate that patients with NET experience fatigue, nausea/vomiting, pain, dyspnea, and sleep disturbance. Anxiety, higher depression, and stress negatively influenced HRQoL. More social support, self-efficacy, and optimism were associated with better HRQoL. Findings from the qualitative studies emphasize that NET-related symptoms and adverse effects of the treatment influence the patients' HRQoL. Conclusion This review identified fatigue, nausea/vomiting, pain, dyspnea, and sleep disturbance as the most important symptoms. The most frequently reported psychosocial factors were anxiety and depression, which influenced HRQoL negatively. Social support and self-efficacy had a positive impact on HRQoL.