The reaction of butane-1,4-diol with allyl chloride in the presence of aqueous sodium hydroxide solution and quaternary ammonium salt (Bu4N+HSO4-) acting as phase transfer catalyst was investigated. The influence on the allylation reaction of the following factors: temperature, time, amount and concentration of the base, and amount of the catalyst was estabilished. 1-Allyloxy-4-hydroxybutane was prepared in 80% yield. 1,4-Diallyloxybutane was obtained in almost quantitative yield - 95%.