Phosphate ester compound of hydroxy acid substituted phenyl ester, preparation method and medical use thereof are provided. The title compound is shown in formula (I), in which Y═C1-4 straight carbon chain, M1 and/or M2=H, alkali metal ion, protonated amine or protonated amino acid. The compound has good water solubility and high stability in its aqueous solution, and it can release 2,6-diisopropylphenol rapidly under the action of enzymes in vivo, which has the effects of sedation, hypnosis and/or anesthesia. By protecting hydroxyl of 2,6-diisopropylphenol in compound of formula (I), the first-pass metabolic activity of 2,6-diisopropylphenol is reduced, so that the synthetic compound can be used for sedation, hypnosis and/or anesthesia.