(S)-(+)-3-Hydroxytetrahydrofuran was prepared from the reaction of (S)-1,2,4-butanetriol under hydrochloric acid modified montmorillonite catalyst. The steps were as follows:To the heatable reactor (with stirring device), 100g (S)-1,2,4-butanetriol, 200mL toluene, 15g hydrochloric acid modified montmorillonite catalyst prepared in were added successively. The reaction was stopped after 4 h at 110°C. After the reaction is finished, it is naturally cooled to room temperature, and the obtained material is filtered to recover the catalyst. After collecting the filtrate, the remaining solvent and by-product water in the filtrate are distilled off to obtain (S)-3-hydroxytetrahydrofuran crude product. Quantitative analysis was carried out by gas chromatography, and the yield was 96.8%. Finally, the (S)-3-hydroxytetrahydrofuran was obtained by rectification and purification.