Objective To study the epidemiological and pathological features of sudden death （SD） in Yunnan Province and to provide scientific evidence for prevention and forensic identification of sudden death. Methods Totally 363 SD cases were collected from the autopsies between 2009 and 2017 in the Forensic Centre of Kunming Medical University. The related factors such as etiology, age, inducing factor, time interval between the onset of disease and death, morbidity season and pathological change were retrospectively analysed. Results The incidence of SD in males was significantly higher than that of females. The peak age was ≥35-55 years. The mortality rate was relatively high within 6 h after the onset of disease. The season order with descending number of deaths was spring, summer, winter and autumn. The top ten causes of SD were coronary heart disease, sudden unexplained death （SUD）, cerebral hemorrhage, acute hemorrhagic necrotic pancreatitis, aortic dissection rupture, cardiomyopathy, pneumonia, pulmonary thromboembolism, amniotic fluid embolism and allergy. Exercise, infusion, surgery, medication and minor injury were the most common predisposing factors of sudden coronary death. Consciousness disorder or coma, chest pain or chest tightness, and abdominal pain were the most common premortem symptoms of sudden coronary death. Conclusion The SD is more common in middle-aged males, which is the key population for the prevention of SD. For the forensic identification and prevention of SD, the attention on SUD should be paid.