The application discloses a preparation method of an
alumina aerogel heat insulation felt, and comprises the following steps: adding an aluminum source precursor into a
ketone substance to form a precursor solution through sufficient
dissolution; adding an
alcohol solvent containing a
silicon source precursor, an amine substance and a catalyst into the precursor solution to form an
alumina sol through uniform stirring; adding a surfactant into the
alumina sol to form an alumina
sol containing a light shielding agent through uniform stirring; adding light shielding agent particles into the alumina sol to form the alumina sol containing the light shielding agent; immersing a
ceramic fiber felt into the alumina sol containing the light shielding agent to perform gel aging, so as to obtain a
fiber felt / gel composite; and performing
drying and heat treatment on the
fiber felt / gel composite, so as to obtain the alumina
aerogel heat insulation felt. The alumina
aerogel heat insulation felt prepared by the method has the advantages of high
temperature resistance, excellent heat insulation performance and good flexibility.