Abstract: The present invention relates to a curing agent composition for epoxy resins comprising (A) a polyamine compound which is a reaction product of a compound having at least one glycidyl group in a molecule with a diamine having a specific structure, (B) a polyether-modified polysiloxane having a surface tension in the range of 19 dyne/cm to 25 dyne/cm and (C) an amino group-modified polysiloxane having a total amine value in the range of 150 mgKOH/g to 650 mgKOH/g which can provide excellent curing performances, excellent performances of epoxy resin cured coating films and excellent physical properties of epoxy resin cured products, an epoxy resin composition comprising said curing agent composition for epoxy resins and an epoxy resin cured product obtained by curing said epoxy resin composition.