The invention discloses a sleep apnea syndrome detecting system. The sleep apnea syndrome detecting system is composed of a sleep respiration detecting device, a processing and diagnosing device, a thermistor sensor, positive electrodes and negative electrodes, wherein the sleep respiration detecting device is composed of a protecting circuit, a resistance type respiration detecting module, an electrocardio signal detecting module, an acceleration detecting module, a oral-nasal respiration detecting module, a processor module and a wireless communication module; the thermistor sensor is used for detecting oral-nasal respiratory airflow; the positive electrodes and the negative electrodes are used for detecting body chest breathing and electrocardio signals. Through the sleep apnea syndrome detecting system, a patient does not need to be hospitalized; the sleep apnea syndrome detecting system is simple and avoids physiological and psychological burdens. The sleep apnea syndrome detecting system can comprehensively detect the respiratory status of different parts of a human body to achieve the aim of sleep apnea syndrome classification and diagnosis, and meanwhile is simple in operation and can be used at home.