In recent years increasing evidence has accumulated about the danger of blue light. Retinal toxicity of blue light has been scientifically established. Its most important mechanisms are retinal pigment epithelium and photoreceptor damage and oxidative stress. The cumulative toxicity of blue light has not yet been shown. However, potentially it is dangerous and can lead to age-related macular degeneration and cataract formation. This issue is of great interest because everyday exposure to short wavelength light has grown with the development of smartphones and tablets as well as with the expanding use of economical light sources such as light-emitting diodes. At the same time, the influence of these blue light sources on health is not known. This article focuses on the information provided by animal experiments and describes the potential influence of blue light on eye health and on the pathogenesis of eye diseases.