The causes of dizziness when lying down and nothing when lying sideways are as follows: First, benign and positional vertigo, also known as otolithiasis, is caused by the precipitation of calcium carbonate crystals in the ear, which stimulates the balloon and ellipsoidal sac in charge of balance when lying down, resulting in transient dizziness, and in severe cases, patients experience visual rotation, nausea, vomiting, etc., and treatment is given to patients for manual reset, etc.; Second, dizziness when lying down and nothing when lying sideways is clinically seen in cervical vertigo caused by some cervical spondylosis. Cervical vertigo, due to the protruding cervical disc affects the blood supply of vertebral artery when lying down, the blood supply of brain is affected and manifested as dizziness, treatment is mainly given to patients traction, acupuncture, massage and other symptomatic treatment; Third, lying down dizziness, side lying nothing is also seen clinically in some chronic, subjective vertigo patients, considered to be caused by psychogenic diseases, if necessary, patients are given psychological guidance and other treatment.