The present invention discloses a poly(terephthalate-co-sebacate) resin composition, comprising the following components: a. poly(terephthalate-co-sebacate); and b. an alkane, which is at least one selected from the group consisting of hexadecane, heptadecane, octadecane, nonadecane and eicosane; wherein a weight content of the alkane is 5ppm-1000ppm based on a total weight of the poly(terephthalate-co-sebacate) resin composition. The present invention controls the content of alkane in the composition within a range of 5ppm-1000ppm by adding an alkane, which not only enables the poly(terephthalate-co-sebacate) resin to have obviously improved blow molding properties, a film thickness range of less than 0.3 µm, and a relative deviation of film thickness of less than 2.0%, thereby guaranteeing a bubble stability and a continuity of blow molding, but also enables the film material to prevent the ink from stripping off the film material, and to prevent excessive ink from adhering to the film material in the printing process, so that the film shows excellent printing performance.