This systematic review evaluates the impact of immune-mediated inflammatory diseases (IMIDs) on sexual function and health-related quality of life (HR-QoL) in both men and women, from a biopsychosocial perspective. Diseases assessed include rheumatoid arthritis, psoriatic arthritis, psoriasis, ankylosing spondylitis, Crohn’s disease, and ulcerative colitis. A total of 42 studies were included following a systematic search in PubMed/MEDLINE. The review adhered to PRISMA guidelines and was registered in PROSPERO (CRD42024518043). Results highlight a high prevalence of sexual dysfunction in IMID patients, significantly impairing quality of life. Assessments were primarily conducted using the Female Sexual Function Index (FSFI) and the International Index of Erectile Function (IIEF). Women, particularly those with rheumatoid arthritis and inflammatory bowel disease, exhibited higher vulnerability, with risk factors being disease severity, pain, depression, and anxiety. These findings underscore the necessity of a multidisciplinary and biopsychosocial approach involving rheumatologists, gastroenterologists, psychologists, and sexologists. Regular assessments and tailored interventions targeting sexual health are essential to optimize outcomes and to address this often overlooked dimension of patient care.