Abstract: A method for recovering a condensable gas from a mixed gas uses a condensable gas recovering apparatus. The apparatus comprises a compressor for compressing a mixed gas comprising a condensable gas and an incondensable gas, a mixed gas separator including a cooler and an adsorbent that adsorbs the incondensable gas, and a vacuum exhauster. The method comprises the steps of introducing the mixed gas highly compressed by the compressor into the mixed gas separator, liquefying and recovering the condensable gas by cooling the mixed gas separator with the cooler while the adsorbent adsorbs the incondensable gas contained in the mixed gas in a high pressure state, and exhausting the incondensable gas from the adsorbent in a low pressure state where the gas in the mixed gas separator has been exhausted by the vacuum exhauster. Therefore, recovery of the condensable gas is carried out with high reliability, and mixing of a large quantity of the condensable gas into the incondensable gas is easily prevented.