Disclosed is a biodegradable polyester composition, where the weight content of a cyclic ester as structurally represented by formula (1) is 100 ppm to 950 ppm based on the total weight of the biodegradable polyester composition, and the weight content of tetrahydrofuran is 3 ppm to 200 ppm based on the total weight of the biodegradable polyester composition. The present invention, by adding the cyclic ester and tetrahydrofuran to the composition, controls the content of the cyclic ester and that of tetrahydrofuran in the composition within a certain range, thus greatly increasing the thermal-oxidative aging resistance of the biodegradable polyester composition; also, a film produced by blow molding or a workpiece produced by injection molding produces a small amount of surface precipitates after being boiled in 95% ethanol at 40 °C for 240 h, has great surface appearance properties, and greatly improves on the phenomenon of poor printing for the biodegradable polyester composition in a printing process, thus allowing the film to express great printing properties.