INTRODUCTION: Parathyroid adenomas can rarely cause spontaneous haemorrhage, which can be life-threatening. Diagnosis is challenging. We present a case and systematic review to define a clearer pattern of symptoms, diagnosis, and treatment. MATERIALS AND METHODS: We conducted a literature search of PubMed, Google Scholar, and Embase using PRISMA guidelines, identifying 38 relevant case reports on spontaneous neck bleeding or haematoma caused by parathyroid adenomas from 1974 to 2020. Data included epidemiology, clinical features, and treatment. One patient treated at our clinic is described. RESULTS: Reviewing 38 articles, we found cervical haematomas from spontaneous bleeding of parathyroid adenoma in 45 patients, comprising 33 women and 12 men. Common symptoms were neck pain, dysphagia, and swelling. Surgery was the primary treatment, with 4.4% requiring tracheotomy. Average hospital stay was 12.5 days, which was mostly complication-free. CONCLUSIONS: Parathyroid adenoma haemorrhage in middle-aged women with neck swelling, pain, and swallowing difficulty should be suspected. Diagnosis involves blood tests and contrast CT. Treatment is adenoma removal, typically without major complications.