A thermo-shrinkable polyester film, comprising: particles dispersed in a polyester resin matrix, wherein the thermo-shrinkable polyester film has a haze of 1.0% or less; a contraction ratio of the thermo-shrinkable polyester film in a main contraction direction is 35 - 80% when it is treated with hot water at 90°C for 10 seconds; a contraction ratio of the thermo-shrinkable polyester film in a direction perpendicular to the main contraction direction is 5% or less when it is treated with hot water at 90°C for 10 seconds; and a number of protrusions having a size of 200 μm or larger distributed in a sample having an area of 1 m x 1 m is 0; wherein the haze is measured based on ASTM D-1003, seven parts being randomly extracted from two peripheral positions and one central position of the thermo-shrinkable polyester film, and thereafter being cut to a size of 5 cm x 5 cm, put into a hazemeter and then irradiated with light having a wavelength of 555 nm to measure their respective haze values (%), and the average value of the five haze values excluding the maximum haze value and the minimum haze value being defined as the haze, wherein the particles dispersed in the polyester resin matrix has an average particle size of 1 - 5 μm, wherein the particles are included in an amount of 30- 150 ppm based on the total weight of the polyester resin matrix, wherein the thermo-shrinkable polyester film comprises an inline coating layer including particles having an average particle size of 80 - 200 nm on a surface layer thereof, wherein the polyester resin matrix includes at least one selected from copolyesters obtained by polymerizing dicarboxylic acid components including one or more dicarboxylic acids, such as terephthalic acid, oxalic acid, malonic acid, succinic acid, adipic acid, suberic acid, azelaic acid, sebacic acid, phthalic acid, iso-phthalic acid, naphthalene dicarboxylic acid and diphenyl ether dicarboxylic acid, with diol components including one or more diols, such as ethylene glycol, neo-pentyl glycol, propylene glycol, trimethylene glycol, tetramethylene glycol, hexamethylene glycol, diethylene glycol, polyalkylene glycol, 1,4-cyclohexane dimethanol; or a mixture of a homopolyester and the copolyester. particles dispersed in a polyester resin matrix, wherein the thermo-shrinkable polyester film has a haze of 1.0% or less; a contraction ratio of the thermo-shrinkable polyester film in a main contraction direction is 35 - 80% when it is treated with hot water at 90°C for 10 seconds; a contraction ratio of the thermo-shrinkable polyester film in a direction perpendicular to the main contraction direction is 5% or less when it is treated with hot water at 90°C for 10 seconds; and a number of protrusions having a size of 200 μm or larger distributed in a sample having an area of 1 m x 1 m is 0; wherein the haze is measured based on ASTM D-1003, seven parts being randomly extracted from two peripheral positions and one central position of the thermo-shrinkable polyester film, and thereafter being cut to a size of 5 cm x 5 cm, put into a hazemeter and then irradiated with light having a wavelength of 555 nm to measure their respective haze values (%), and the average value of the five haze values excluding the maximum haze value and the minimum haze value being defined as the haze, wherein the particles dispersed in the polyester resin matrix has an average particle size of 1 - 5 μm, wherein the particles are included in an amount of 30- 150 ppm based on the total weight of the polyester resin matrix, wherein the thermo-shrinkable polyester film comprises an inline coating layer including particles having an average particle size of 80 - 200 nm on a surface layer thereof, wherein the polyester resin matrix includes at least one selected from copolyesters obtained by polymerizing dicarboxylic acid components including one or more dicarboxylic acids, such as terephthalic acid, oxalic acid, malonic acid, succinic acid, adipic acid, suberic acid, azelaic acid, sebacic acid, phthalic acid, iso-phthalic acid, naphthalene dicarboxylic acid and diphenyl ether dicarboxylic acid, with diol components including one or more diols, such as ethylene glycol, neo-pentyl glycol, propylene glycol, trimethylene glycol, tetramethylene glycol, hexamethylene glycol, diethylene glycol, polyalkylene glycol, 1,4-cyclohexane dimethanol; or a mixture of a homopolyester and the copolyester.