Strabismus is a disease of the extraocular muscles that prevents both eyes from looking at the target at the same time, and can be divided into two categories: common strabismus and paralytic strabismus. The former is characterized by a deviated eye position, no obstruction of eye movement and no double vision, while in the case of paralytic strabismus, there is limited eye movement, double vision, and symptoms such as vertigo and nausea. The causes of strabismus are complex, and the main treatment is to address the causes and surgery. Strabismus is first and foremost an effect of appearance, which is the main motivation for patients to seek medical attention, along with headaches, eye pain, and photophobia, which are caused by the constant use of neuromuscular reserves and result in eye muscle fatigue. More importantly, strabismus affects the visual function of both eyes, and in severe cases there is no good stereo vision, which is an advanced visual function that only humans and advanced animals have, and is one of the prerequisites for people to do fine work, and without good stereo vision, there will be many limitations in learning and employment. Most people with strabismus also have amblyopia, and because of the long-term gaze of one eye, the other eye will cause disuse vision loss or stop developing, and even with glasses, normal vision cannot be achieved. Strabismus in childhood also affects the skeletal development of the whole body, such as the compensatory head position of congenital paralysis strabismus, which can cause contracture of the neck muscles and pathological curvature of the spine, and asymmetric facial development. The principle of treatment for strabismus is early detection and early treatment, firstly for amblyopia to promote good potential development of both eyes, and secondly for correction of the skewed eye position. The treatment methods include: wearing glasses, wearing eye shields, eye axis correction training, eye muscle surgery and a combination of various methods.