The preparation of silica-titania aerogel by supercritical impregnation of titanium isopropoxide (TP) or modified with acetylacetone (TPAA) using flow type apparatus was performed. The influence of the physical state of TP/CO 2 TPAA/CO 2 mixture was investigated. Homogeneous and rapid impregnation on monolithic silica alcogel was achieved using supercritical TP/CO 2 or TPAA/CO 2 mixtures at the single phase condition (353 K, 20 MPa). Crystallization of impregnated titania using this system was attained by increasing temperature during the depressurization process after impregnation.