Abstract: The present application discloses a thermally insulating aerogel vacuum composite panel and a preparation method thereof. The preparation method includes the following steps: (1) mixing TEOS solution and a metal particle, adding a hydrophobic agent, mixing, adding ammonium trifluoroacetate solution dropwise until completely gelating to obtain a metal aerogel precursor; (2) adding the metal aerogel precursor into an acid replacement solution for replacement for 1-24 h to obtain a gel; (3) washing the gel with deionized water to obtain a neutral gel; (4) soaking the neutral gel obtained in step (3) in a first organic resin solvent; (5) pouring the neutral gel into a substrate with honeycomb structure, and aging for re-gelating to obtain a modified panel; (6) drying the modified panel to obtain a honeycomb panel; and (7) aging the honeycomb panel at room temperature for 1-24 h to obtain the vacuum composite panel.