The present invention relates to a process for purifying 1,4-butynediol, which comprises compressing 1,4-butynediol to from 50 to 1500 bar, depressurizing it, waiting for phase separation to occur after depressurization and separating off the bottom phase, and a process for the hydrogenation of 1,4-butynediol to 1,4-butenediol and 1,4-butanediol using the purified 1,4-butynediol.