To provide a precursor for a polyesterimide also having a high glass transition temperature, extremely low linear thermal expansion coefficient, extremely low water-absorption ratio, extremely low moisture absorption expansion coefficient, sufficient toughness, high thermal stability and flame resistance, and a polyesterimide.

The polyesterimide precursor is obtained from an ester group-containing tetracarboxylic acid dianhydride and a diamine. The ester group-containing tetracarboxylic acid dianhydride is an ester group-containing tetracarboxylic acid dianhydride represented by formula (1). (wherein R1-R8 each independently represents a hydrogen atom, a 1-6C linear or branched alkyl group or a 1-6C linear or branched alkoxy group, and Y represents an ester group).