A method for producing a silica aerogel includes a gelation step of adding a monoalkyltrialkoxysilane to an acidic aqueous solution containing a surfactant to prepare a sol, and then gelating the sol to prepare a wet gel. The method further includes a separation step of immersing the wet gel in a solvent mixture of a first solvent and a second solvent immiscible with the first solvent. The first solvent has an ETN value of 0.5 or less, and the second solvent has an ETN value between those of the first solvent and water. The method further includes a drying step of drying the wet gel at a temperature lower than a critical temperature of the first solvent under a pressure lower than a critical pressure of the first solvent to remove the first solvent from the wet gel.