The invention belongs to the technical field of macromolecular materials and medicaments, and relates to a physical cross-linking hydrogel composition and a preparation method and application thereof. The composition is a mixture of two or more polymers, and the aqueous system of the composition has the temperature-sensitive reversible gelling property; when the temperature is lower than a sol-gel conversion temperature, the mixture can be dissolved in water; and when the temperature is higher than the sol-gel conversion temperature, the aqueous solution of the mixture forms gel, and the process is reversible, wherein the polymers comprise a block copolymer consisting of polyethylene glycol serving as a hydrophilic block and degradable polyester serving as a hydrophobic block. The aqueoussolution of the composition can be applied to warm-blooded animals through non-stomach intestinal tract, eye, subcutaneous, muscle, vagina, urethra, nasal cavity or lung, forms gel at physiological related temperature, and also can be applied in a gel form. The release speed can be regulated by changing the mixing proportion, polymer composition, molecular weight and polydispersity.