The invention discloses a sleep monitoring system and method. The sleep monitoring system comprises a pressure sensor, a CO2 sensor, an oxygenator, a temperature sensor, a temperature regulator, a breath sensor, a pulse sensor, a brain wave sensor, a controller, a wireless communication module and a signal processing unit, the controller is used for receiving body pressure signal, CO2 concentration signal, temperature signal, breathing frequency, carotid artery pulse signal and brain wave signal which are transmitted to the signal processing unit through the wireless communication module, thecontroller analyzes the CO2 concentration signal and the temperature signal to judge whether to start the oxygenator and the temperature regulator or not, and the signal processing unit comprehensively analyzes the body pressure signal, the breathing efficiency, the carotid artery pulse signal and the brain wave signal. By the sleep monitoring system and method, the problem of inconvenience in operation caused by existing sleep monitoring devices can be solved, and sleep quality can be improved.