Amino-functionalized titanosilicate materials were prepared as an alternative for developing efficient adsorbents of azo dyes. Functionalization of the titanosilicates with ethylenediamine groups was carried out via the sol-gel process, using the hydrolytic route. The obtained xerogels were characterized by thermal analysis, elemental chemical analysis, infrared absorption spectroscopy, textural analysis, transmission electron microscopy, and energy-dispersive X-ray spectroscopy. Adsorption of the azo dye Orange II from aqueous solutions by the functionalized titanosilicate materials was investigated by adsorption isotherms and kinetic studies. The Langmuir and Freundlich adsorption models were applied to describe the experimental isotherms and to obtain the isotherm constants.