The present invention relates to the preparation of an extract of the crustacean Artemia salina and to the use thereof to treat diseases of the ocular surface. The invention describes the application of the extract mainly by means of soaps, eyedrops, eye solutions, eye washes, aerosols, in the presence of unguents, creams, gels or contact lenses, inter alia. The application of the Artemia salina extract is efficient for treating pathologies consistent with ocular dryness (dry eye) and the manifestations thereof such as the appearance of injuries or ulcers on the ocular surface or infections caused by microorganisms and associated with dry eye, also on the ocular surface.