A cornea center positioning method for excimer laser keratomileusis includes the following steps of establishing a horizontal offset model and a vertical offset model by way of measuring the pupil diameter and offset of the pupil center relative to the center of the corneal vertex under different luminance levels, and inputting data of the established models into a laser keratomileusis machine with an eye tracking system, which can dynamically track the pupil location and keep the ablation center precisely at the center of the corneal vertex.