The present invention relates to a temperature-sensitive carrier for carrying a physiologically active substance and a preparation method thereof. Specifically, the temperature-sensitive carrier according to the present invention comprises an amphiphilic biodegradable block copolymer containing polysaccharide or polysaccharide and succinic anhydride as a hydrophilic block and polylactide as a non-ionic block. A hydrophilic polymer-polylactide copolymer according to the present invention forms a stable complex with a physiologically active substance such as protein, polynucleotide and the like in vivo via ionic bonding and temperature-sensitive hydrophobic bonding. Therefore, a copolymer according to the present invention can facilitate in vivo delivery of a physiologically active substance and used as an in vivo drug delivery system.
