Introduction This report aims to describe the epidemiology, clinical presentation, diagnostic workup, treatment, and rehabilitation, natural course, and possible risk factors of the rare entity spontaneous iliopsoas tendon rupture. Methods One case of spontaneous iliopsoas tendon rupture was encountered. The patient was followed during the hospital stay, her journal was later reviewed, and one telephone follow-up after 90 days was performed. Structured reviews of the literature in the PudMed and Micromedex databases were performed. Results The patient recovered fully within 6 weeks of conservative treatment with small doses of acetaminophen and opioid. The literature reviews yielded 14 previously reported spontaneous iliopsoas tendon ruptures but no strong evidence regarding possible risk factors. Conclusion Spontaneous iliopsoas tendon rupture is a rare event, typically occurring in the elderly female. MRI is generally diagnostic, but signs are also often present on CT scans and sometimes even on plain X-ray. Conservative treatment has an excellent prognosis of full recovery within 6 weeks. The evidence on possible risk factors is scarce and conflicting.