To provide a polyester resin composition being able to maintain a long-wavelength ultraviolet-blocking effect for a long period of time, ensuring high solubility for a solvent, and having excellent light resistance. A polyester resin composition comprising a compound represented by the following formula (1) and a polyester resin: wherein each of R 1a , R 1b , R 1c , R 1d and R 1e independently represents a hydrogen atom or a monovalent substituent excluding OH, at least one of the substituents represents a substituent having a positive Hammett's Ãp value, and the substituents may combine with each other to form a ring； and each of R 1g , R 1h , R 1i , R 1j , R 1k , R 1m , R 1n and R 1p independently represents a hydrogen atom or a monovalent substituent, and the substituents may combine with each other to form a ring.
