It is possible to be myopic again after full femtosecond laser surgery, divided into the following cases: 1, the degree before full femtosecond laser surgery is not stable: the most common kind of reason is that the degree before doing full femtosecond laser surgery is not stable, general laser surgery requirements can not exceed 50 degrees of degree growth per year, preferably above the age of 18. Some are because of special needs, the degree is not stable, and also grow more than 100 degrees per year, after doing full femtosecond laser surgery, the corrected vision may be normal at that time, but may also grow about 100 degrees per year, and over time and myopia; 2, full femtosecond laser surgery undercorrection: that is, after the surgery did not reach the normal degree, may also retain 100 degrees, which is caused by surgery; 3. There is a tendency of cone cornea: not found in the preoperative examination, with the development of cone cornea may be myopic again, which is a special corneal disease.