There are many reasons that can cause sleep paralysis, including sleep disorders, incorrect sleep posture, drug effects, anxiety and depression, as follows: 1. Sleep disorders: poor sleep quality or insufficient sleep time is common, such as patients with excessive dreams, early awakening, difficulty falling asleep or the habit of staying up late or jet lag; 2. Incorrect sleep posture: for example, if there is a long-term lying down, hands or other objects pressed on the 3, drug effects: for example, after drinking alcohol, sleep paralysis is likely to occur; 4, anxiety and depression: these emotional abnormalities are also a great cause of sleep paralysis, especially patients with anxiety disorders, manifested as thinking about things, the brain can not be quiet, often have difficulty falling asleep, the brain is in a more excited state for a long time, and sleep paralysis is likely to occur when the pressure is high.