Objective: We aimed to explore the prevalence of somatic symptom disorder (SSD) according to DSM-5 criteria in Chinese outpatients from general hospital departments. Methods: This multicentre cross-sectional study enrolled 699 patients from outpatient departments, including the neurology, gastroenterology, Traditional Chinese Medicine [TCM] and psychosomatic medicine departments, in five cities in China. The structured clinical interview for DSM-5 (SCID-5) for SSD was administered by trained clinical professionals to diagnose SSD. Results: SSD was diagnosed in 33.8% (236/697) of all enrolled patients. The prevalence of SSD differed significantly among the departments (chi(2) = 34.049, df = 2, p <= 0.001). No differences were found between SSD patients and non-SSD patients in terms of gender, residence, marital and living statuses, family income, education, employment status and lifestyle factors. However, patients with SSD reported higher levels of depression, health-related and general anxiety, lower physical and mental quality of life, higher frequency of doctor visits, increased time devoted to physical symptoms and longer duration of somatic symptoms. In a binary linear regression analysis, SSD was significantly associated with an increase in health-related anxiety, time devoted to symptoms and impact of somatic symptoms on daily life. The explained variance was Nagelkerke R-2 = 0.45. Conclusion: There is a high prevalence of SSD in Chinese general hospital outpatient clinics. The diagnosis is associated with high levels of emotional distress and low quality of life. There is a danger of over-diagnosis if we include the mild and moderate forms of SSD. Future studies are warranted to investigate the prevalence of SSD in inpatient departments and the development of psychological interventions for these patients.