The corner of the mouth shaking is caused by the following: 1, caused by excessive excitement, people in excessive excitement will cause plant nerve dysfunction, resulting in sympathetic excitation, so that the muscle appears involuntary tremor, strong contraction and other phenomena, manifested in the corner of the mouth area will appear the corner of the mouth shaking, through certain mental regulation can be significantly improved; 2, lip shaking may be due to facial muscle spasm, ectopic excitation and facial nerve conduction is caused. It can be caused by aneurysm compression, arteriovenous malformation, brain tumor and facial nerve root, but also partly related to tumor, surgery, trauma, inflammation, lip turning and facial muscle twitching.