Polyester resin composition

The present invention provides a polyester resin composition with excellent transparency and flexibility, and with high thermal resistance, which is capable of suppressing leaking of oligomer to be low and renders stick between compacts on pellets to be difficult to occur. The polyester resin composition of this invention contains polyester obtained by bringing a dicarboxylic acid component including (a) an alicyclic dicarboxylic acid of 75 to 98 mole%, and (b) a dimer acid of 2 to 25 mole%, and a diol component including (c) an alicyclic diol of 75 mole% or more into polymerization reaction. (a)the alicyclic dicarboxylic acid is preferably an alicyclic dicarboxylic acid with a carbon number of 5 to 30. With respect to the total amount of the trans- and cis- form components of the (a) alicyclic dicarboxylic acid included in the polyester resin composition, the ration of the trans-form component is preferably 80% or more. The (b) dimer acid is preferably a dimer acid with a carbon number of 36 or a carbon numb