The heat insulating composite aerogel material consists of silica aerogel, titania as infrared opacifier and reinforcing fiber in the weight ratio of 1 to 0.1-0.7 to 0.7-3. Its preparation process includes compounding sol with silanolate, surface modifier, titanolate, alcohol solvent, acid catalyst and alkaline catalyst in certain proportion; soaking fiber felt or prefabricated fiber part in the sol; and supercritical fluid drying. The material of the present invention has high blocking effect on solid heat transfer, air heat transfer and infrared radiation heat transfer, excellent hydrophobicity, simple preparation process, low cost, mechanical strength over 2 MPa, and wide application range, and may be used in strict heat protection condition in aeronautics, astronautics, military and civil uses.