Biodegradable polyester composition and use thereof

The present invention discloses a biodegradable polyester composition, wherein the biodegradable polyester composition comprises the following components in parts by weight: i) 58 to 80 parts by weight of an aliphatic-aromatic copolyester; ii) 20 to 32 parts by weight of starch; and iii) 0 to 10 parts by weight of a processing agent. The present invention unexpectedly found by research that by using an aliphatic-aromatic copolyester in which an amount of aromatic carboxylic acid accounts for a total amount of diacid is 44 mol % to 48 mol % as a matrix resin, where the aliphatic-aromatic copolyester has a crystallization peak width D of 5° C. to 16° C., and by using starch of which a particle size D (50) is 2 μm to 12 μm as the other phase, and meanwhile by adding a specific amount of a processing agent, the polyester composition prepared has excellent transversal and longitudinal tear strengths, and the polyester composition has a biodegradation rate of 90% or more during the 12-week degradation test, satisfying the industrial compost.