The poor light sensitivity of full-month-old babies’ eyes may be caused by imperfect development, or it may be caused by amblyopia and other diseases. 1. Imperfect development: for full-month-old babies, because the retina development is not yet perfect, so the eyes are less sensitive to light stimulation, mostly considered a physiological phenomenon, can be observed for the time being. 2. Amblyopia: Amblyopia refers to a disease in which the best corrected visual acuity of one eye or both eyes is lower than that of normal children of the corresponding age due to abnormal visual experiences such as monocular strabismus, refractive error, high refractive error, and shape deprivation during the period of visual development, so that poor sensitivity to light in the eyes of the affected children can be found through examination. It is recommended that children with poor eye vision should consult a hospital in time to complete the examination, identify the specific cause, and follow the doctor’s instructions to choose the appropriate treatment.