The present invention provides a method and device for detecting sleep apnea, which overcomes the current defect that it is hard to distinguish the type of sleep apnea. The method comprises: monitoring an instantaneous output power and an instantaneous rotation speed of a motor for delivering air in a breathing device (S110) according to the instantaneous output power and the instantaneous rotation speed of the motor, obtaining an airway flow reference value represented for the air in an upper airway of a user using the breathing device (S120) when it is determined that the user currently has no spontaneous breathing according to the airway flow reference value, and corresponding duration has reached a preset time threshold value, determining the user to be in an apnea state (S130) judging whether the upper airway of the user is clear (S140) and determining the apnea of the user to be central apnea (S150) or obstructive apnea (S170) depending on whether the upper airway of the user is clear. The method and device can accurately and effectively distinguish the type of sleep apnea.