The present invention discloses a PBAT resin composition comprising following components: (a) poly(butyleneadipate-co-terephthalate); (b) iron element; wherein, based on a total weight of the PBAT resin composition, a weight content of the iron element is 1 ppm-500 ppm. By adding iron-containing compounds into the composition and controlling the content of the iron element in a range of 1 ppm-500 ppm in the composition, a speed of reaction of aromatic structure in the PBAT resin under a hot and humid condition can be postponed, so that after the prepared PBAT resin composition is aged in boiling water for 24 hours and 48 hours, a variation of b-value is less than 2. The PBAT resin composition has obviously improved color stability in resistance to boiling water aging.